This case study describes a project to improve the average speed to answer calls at a retail business. The project team analyzed call data, identified root causes such as call type and time of day, and implemented cross-training and staffing changes. These improvements reduced customer downtime costs by $150,000 annually and increased the process sigma level. Key tools used in the project included data collection, analysis of call times, and control charts to monitor ongoing performance.
Lean Six Sigma case study improves call center speed
1. Lean Six
Sigma Group
Lean Six Sigma Case Study
Executive Overview
International Standards for Lean Six Sigma (ISLSS)
2. “Descriptive Project Title”
Process Capability Analysis for Average Spee
LSLUSL
ST
LT
-100 0 100 200 300 400
LSL USL
ST
LT
0 10 20 30 40
Customer Profile: 28,000 Retail Business
Business Problem & Impact:
USL
Target
Average speed to answer (ASA) was 1 minute. As call volumes
LSL
Mean
increased 30% with a recent acquisition, end user downtime Sample was
N
StDev (ST)
costing the company US$500K annually. The target average StDev speed (LT)
to
answer was under 30 seconds.
Measure & Analyze:
Data Collection: Speed to answer on all calls was measured. The
existing process sigma was 2.4.
Root Causes: Nature of problem and time of call were identified as root
causes.
USL
T arget
LSL
Mean
Sample N
StDev (ST )
StDev (LT )
Improve & Control:
Cross-training on call types was performed and staffing was arranged
around peak call times. Metrics are reviewed weekly and posted to an
IT dashboard.
Cp
CPU
CPL
Cpk
Cpm
Pp
PPU
PPL
Ppk
PPM < LSL
PPM > USL
PPM T otal
PPM < LSL
PPM > USL
PPM T otal
PPM < LSL
PPM > USL
PPM T otal
20.0000
*
0.0000
14.7929
169
3.38716
4.61648
0.98
0.51
1.46
0.51
*
0.72
0.38
1.07
0.38
0.00
130177.51
130177.51
6.29
62109.19
62115.48
129673.00
130349.79
Proces s Data
Potential (ST ) Capabi l i ty
Overal l (LT ) Capabi l i ty Observed Performance Expec ted ST Performance Expec ted LT Performance
Cp
CPU
CPL
Cpk
Cpm
Pp
PPU
PPL
Ppk
PPM < LSL
PPM > USL
PPM Total
PPM < LSL
PPM > USL
PPM Total
PPM < LSL
PPM > USL
PPM Total
20.0000
*
0.0000
71.4444
117
38.9880
50.6272
0.09
-0.44
0.61
-0.44
*
0.07
-0.34
0.47
-0.34
0.00
948717.95
948717.95
33440.39
906498.25
939938.64
79094.94
845218.98
924313.92
Process Data
Potential (ST) Capability
Overall (LT) Capability Observed Performance Expected ST Performance Expected LT Performance
Results/Benefits
After the 3 month project, the customer saved US$150K, or 30%, as a
result of reduced end user downtime.
Process Capability
– Before
Process Capability
– After
A Savings of US $150k in 20XX
Create Candor in the Workplace with Jack Welch
Video by Stanford Graduate School of Business
International Standards for Lean Six Sigma (ISLSS) 2
3. Project “Storyboard”
Example
Enter Key Slide Take Away (Key Point) Here
How a Passionate Lean Thinking Enterprise is Developed by Gemba Academy
International Standards for Lean Six Sigma (ISLSS)
4. Lean Six
Sigma Group
Lean Six Sigma Case Study
Backup Slides
International Standards for Lean Six Sigma (ISLSS)
5. Project Charter
Problem/Goal Statement
Problem: Describe problem in non-technical terms
Statement should explain why project is important; why
working on it is a priority
Goal: Goals communicate “before” and “after” conditions
Shift mean, variance, or both?
Should impact cost, time, quality dimensions
Express goals using SMART criteria
Specific, Measurable, Attainable, Resource
Requirements, Time Boundaries
Explain leverage and strategic implications (if any)
Financial Impact
Tollgate Review Schedule
Team
Scope:
In-Scope/Out-of-Scope
(Process Start/Stop
State financial impact of project
Expenses
Investments (inventory, capital, A/R)
Revenues
Separate “hard” from “soft” dollars
State financial impact of leverage opportunities (future
projects, replication opportunities, project iterations)
PES Name Project Executive Sponsor (if different from PS)
PS Name Project Sponsor/Process Owner
DC Name Deployment Champion
GB/BB Name Green Belt/Black Belt
MBB Name Master Black Belt
Core Team Role % Contrib. LSS Training
Team Member 1 SME XX YB
Team Member 2 TM XX GB
Team Member 3 SME XX PS
Extended Team
Team Member 1 BFM XX Not Trained
Team Member 2 IT XX Not Trained
Tollgate Scheduled Revised Complete
Define: XX/XX/XX - XX/XX/XX
Measure: XX/XX/XX XX/XX/XX XX/XX/XX
Analyze: XX/XX/XX XX/XX/XX XX/XX/XX
Improve: XX/XX/XX XX/XX/XX XX/XX/XX
Control: XX/XX/XX XX/XX/XX XX/XX/XX
Review high-level schedule milestones here:
Phase Completions
Tollgate Reviews
Enter Key Slide Take Away (Key Point) Here
How Hoshin Planning helps Organizations Video by iNexusTV1
International Standards for Lean Six Sigma (ISLSS) 5
6. Measure Overview
CTQ: ?
Unit (d) or Mean (c): ?
Defect (d) or St. Dev. (c): ?
PCE%: ?
DPMO (d): ?
Sigma (Short Term): ?
Sigma (Long Term):?
MSA Results: show the percentage result of the GR&R,
AR&R or other MSA carried out in the project
Root cause:
Quick Win #1
Root cause:
Quick Win #2
Root cause:
Quick Win #3
Observation
Individual Value
1 28 55 82 109 136 163 190 217 244
40
35
30
25
20
UC L=37.70
_
X=29.13
LC L=20.56
Observation
Moving Range
1 28 55 82 109 136 163 190 217 244
10.0
7.5
5.0
2.5
0.0
UC L=10.53
__
MR=3.22
LC L=0
I-MR Chart of Delivery Time
Detailed process mapping
MSA
Value Stream Mapping
Data Collection Planning
Basic Statistics
Process Capability
Histograms
Time Series Plot
Probability Plot
Pareto Analysis
Operational Def.
5s
Pull
Control Charts
Enter Key Slide Take Away (Key Point) Here
6
Process Capability Graphical Analysis
Root Cause / Quick Win Tools Used
Gemba Training Video by Gemba Academy
International Standards for Lean Six Sigma (ISLSS)
7. Analyze Overview
Value Add Analysis - Current State
80
60
40
20
0
Takt Time = 55
1 2 3 4 5 6 7 8 9 10
Task #
Task Time (seconds)
CVA Time BVA Time NVA Time
Root cause:
Effect
Root cause:
Effect
Root cause:
Effect
Value Add Analysis
One-Way ANOVA
Two-Way ANOVA
Pareto Plots
Simple Linear Regression
Multiple Regression
Test for Equal Variance
Scatter Plots
C&E Matrix
Complexity
Cause & Effect Diagram
Kaizen/Quick Wins
FMEA
Control/Impact Chart
T-Test
Other
Hypothesis Test
(ANOVA, 1 or 2 sample t - test, Chi Squared,
Regression, Test of Equal Variance, etc)
Factor (x)
Tested
p Value Observations/Conclusion
Example: ANOVA Location 0.030
Significant factor - 1 hour driving time from DC
to Baltimore office causes ticket cycle time to
generally be longer for the Baltimore site
Example: ANOVA Part vs. No Part 0.004
Significant factor - on average, calls requiring
parts have double the cycle time (22 vs 43
hours)
Example: Chi Squared Department 0.000
Significant factor - Department 4 has digitized
addition of customer info to ticket and less
human intervention, resulting in fewer errors
Example: Pareto Region n/a
South region accounted for 59% of the defects
due to their manual process and distance from
the parts warehouse
Describe any other observations about the root cause (x) data
Enter Key Slide Take Away (Key Point) Here
Analyze Tools using SigmaXL Virtual Menus Training Video by SigmaXL Inc.
7
Hypothesis Tests Value-Add Analysis
Root Cause / Effect Tools Used
International Standards for Lean Six Sigma (ISLSS)
8. Improve Summary
Vital X (root cause) Proof of Causation
Practical Solution (process change
to address X)
Operating
Tolerances for X
Client IT need to reverify
all exit data received from
Client HR
Average delay between
reception of information
from Client HR until it
reaches NT Admin or
general admin
Eliminate process - Place accountability
on Client HR for information placed into
new database.
n/a
E-mail vendor's contract
with Client
The SLA has a range of 3-
5 business days for the
completion of a delete
request
E-mail vendor instituted new web
interface for all add/delete requests,
vastly improving request processing
time.
1 - 2 days
E-mail vendor's contract
with Client
The SLA has a range of 3-
5 business days for the
completion of a delete
request
E-mail vendor instituted new web
interface for all add/delete requests,
vastly improving request processing
time.
1 - 2 days
How the solution was determined:
What was the solution selection tool used?
What project management tools were used?
Cost/benefit analysis?
Include any other tools or methods used
1. ?
2. ?
3. ?
4. ?
5. ?
Enter Key Slide Take Away (Key Point) Here
8
Solution Selection Criteria Pilot and Implementation Plan
The 3 Key Secrets of Strategy Execution (Paul Docherty) Video by i-nexus
International Standards for Lean Six Sigma (ISLSS)
9. Control Summary
?
?
?
?
?
Documentation
Provide any necessary training
Translation project within/ outside of region/function:
Any resulting spin-off projects initiated
Any Replication in other locations?
Communication:
Communicate project results with customer
Communicate results with the business
Include text here to explain
highlights of the plan to monitor and
respond to variation in y’s and x’s
Baseline Improved
Units ? ?
Defects ? ?
DPMO ? ?
Mean* ? ?
PCE% ? ?
Std. Deviation* ? ?
Sigma (ST) ? ?
Sigma (LT) ? ?
?
?
?
?
?
Summarize benefits to the
internal/external customers here.
Start tracking benefits from date of
implementation of Improve Phase
Improvements.
Enter Key Slide Take Away (Key Point) Here
9
Control/Response Plan Highlights Benefits of Project
Sigma Levels/Improvements Communication & Translation
Standard Work Training Video by Gemba Academy
International Standards for Lean Six Sigma (ISLSS)
10. Business Impact
State financial impact of future project leverage opportunities
Separate “hard or Type 1” from “soft Type 2 or 3” dollars
Annual Estimate Replicated Estimate
Revenue
Enhancement
• Type 1: ?
• Type 2: ?
• Type 3: ?
• Type 1: ?
• Type 2: ?
• Type 3: ?
Expenses
Reduction
• Type 1: ?
• Type 2: ?
• Type 3: ?
• Type 1: ?
• Type 2: ?
• Type 3: ?
Loss Reduction • Type 1: ?
• Type 2: ?
• Type 3: ?
• Type 1: ?
• Type 2: ?
• Type 3: ?
Cost Avoidance • Type 1: ?
• Type 2: ?
• Type 3: ?
• Type 1: ?
• Type 2: ?
• Type 3: ?
Total Savings • Type 1: ?
• Type 2: ?
• Type 3: ?
• Type 1: ?
• Type 2: ?
• Type 3: ?
Floyd Boilanger CFO Lean Six Sigma Interview National Energy Technology Lab
10
Enter Key Slide Take Away (Key Point) Here
International Standards for Lean Six Sigma (ISLSS)
11. Business Impact Details
Type 1: Describe the chain of causality that shows how you determined the Direct Cash Flow. Tell the story
with cause & effect relationships, on how the proposed change should create the desired financial result ($) in
your project.
Show the financial calculation savings and assumptions used.
Assumption #1 (i.e. source of data, clear Operational Definitions?)
Assumption #2 (i.e. hourly rate + incremental benefit cost + travel)
Type 2: Describe the chain of causality that shows how you determined the Labor Efficiency savings. Tell the
story with cause & effect relationships on how the change should create the desired financial result ($).
Show the financial calculation savings and assumptions used.
Assumption #1 (i.e. Labor rate used, period of time, etc…)
Assumption #2 (i.e. contractor hrs or FTE, source of data, etc…)
Describe the Type 3 Business Impact(s) areas and how these were measured (i.e. Cost/Risk Avoidance)
Assumption #1 (i.e. project is driven by the Business strategy?)
Assumption #2 (i.e. Customer service rating, employee moral, etc…)
Other Questions
Stakeholders agree on the project’s impact and how it will be measured in financial terms?
What steps were taken to ensure the integrity & accuracy of the data?
Has the project tracking worksheet been updated?
11
Enter Key Slide Take Away (Key Point) Here
How to Calculate ROI Training Video by Mike Turco
International Standards for Lean Six Sigma (ISLSS)
12. Lessons Learned
1. ?
2. ?
3. ?
4. ?
5. ?
6. ?
7. ?
8. ?
9. ?
10.?
Enter Key Slide Take Away (Key Point) Here
Learn the 7 Quality Control Tools Training Video by Gemba Academy
International Standards for Lean Six Sigma (ISLSS) 12
13. Project Contributors
Steering Team Support Team
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
Project Ownership Team Deployment Team
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
<Name>: <Contribution>
Enter Key Slide Take Away (Key Point) Here
What does a good Leader or Coach do? (Jeff Liker) Video by George Trachilis
International Standards for Lean Six Sigma (ISLSS) 13
14. Lean Six
Sigma Group
Lean Six Sigma
Additional Resources
How to Upgrade to SigmaXL Video by SigmaXL Inc.
International Standards for Lean Six Sigma (ISLSS)
15. Lean Six Sigma Tollgate
Template Notes
The Lean Six Sigma Tollgate Templates are:
Free and intended as a guide in documenting a Lean Six Sigma
Project. I grant permission for you to modify these templates to meet
the specific needs of your process improvement project.
Instructional - a video has been linked to each Template, I selected a
mix of videos from Thought Leaders in the Lean Six Sigma Group.
I included reference links to all video’s should you want to learn more
information. Also included guidelines in the Note’s section of each
slide.
Efficient and Effective – Placeholders for Graphic or Video Examples
for various tools and methods across each DMAIC Phase.
How to Use These Templates:
Collaboratively – use as a guide, reuse templates independently or
across phases as needed, and change the order as needed to best
capture the execution of Lean Six Sigma in each phase, and
summarize in the final Case Study.
Use as a Communication tool, and document your findings and
results.
15
My name is Steven
Bonacorsi, Author of the
Lean Six Sigma Tollgate
Templates, President of
the International
Standard for Lean Six
Sigma (ISLSS), and
Owner of the LinkedIn
Lean Six Sigma Group.
Replace the content of this slide with images or video’s
related to your process improvement project
International Standards for Lean Six Sigma (ISLSS)
16. Lean Six Sigma Resources
16
Lean Six Sigma Group: https://www.linkedin.com/groups/Lean-Six-Sigma-37987
Lean Six Sigma Subgroups: https://www.linkedin.com/groups?subgroups=&gid=37987
International Standard for Lean Six Sigma (ISLSS): http://www.islss.com
Best Wishes in Continuously Improving Your Business Processes
– Steven Bonacorsi, Certified Lean Six Sigma Master Black Belt
International Standards for Lean Six Sigma (ISLSS)
i-nexus: http://www.i-nexus.com
Strategy Execution Community LinkedIn Group
https://www.linkedin.com/groups/Strategy-Execution-Community-3725091
SigmaXL: http://www.sigmaxl.com
SigmaXL LinkedIn Group: https://www.linkedin.com/groups/SigmaXL-1812101?gid=1812101
Gemba Academy http://www.gembaacademy.com Lean CEO Group:
Gemba Academy LinkedIn Group: https://www.linkedin.com/groups/Gemba-Academy-1844998?gid=1844998
PEX Network http://www.processexcellencenetwork.com
PEX Network & IQPC - Lean Six Sigma & Process Excellence for Continuous Improvement
Lean Leadership Institute: http://www.LeanLeadership.guru/books.html The Toyota Way Group
17. Lean Six Sigma Groups
(Click Logo’s to Join Group)
Lean Six Sigma Group
Each Week, the Lean Six Sigma Group Grows +1,500 New Members; +2,000 Lean
17
Six Sigma Jobs; +200 Discussions; +500 Comments
+280,000 Members – Come Join the Conversation
International Standards for Lean Six Sigma (ISLSS)
18. Lean Six Sigma Resource Blogs
(Click Logo’s to Follow Blogs)
18
See Notes Section for Links to Lean Six Sigma Group Contributors
International Standards for Lean Six Sigma (ISLSS)
19. Lean Six Sigma Executive Overview
Video References – Set 22
Create Candor in the Workplace
with Jack Welch Video by Stanford
Graduate School of Business
How a Passionate Lean Thinking
Enterprise is Developed by
Gemba Academy
Floyd Boilanger CFO Lean Six
Sigma Interview
National Energy Technology Lab
Analyze Tools using
SigmaXL Virtual Menus
Video by SigmaXL Inc.
Gemba Training Video
by Gemba Academy
19
Join the Lean Six Sigma Jobs Group:
http://www.linkedin.com/groups?gid=2161051
International Standards for Lean Six Sigma (ISLSS)
How Hoshin Planning
helps Organizations
Video by iNexusTV1
The 3 Key Secrets of Strategy
Execution (Paul Docherty) Video
by i-nexus
Standard Work Video by
Gemba Academy
20. Lean Six Sigma Executive Overview
Video References – Set 23
20
What does a good Leader or
Coach do? (Jeff Liker) Video by
George Trachilis
Join the Careers in Operational Excellence Group:
http://www.linkedin.com/groups?gid=3723227
International Standards for Lean Six Sigma (ISLSS)
How to Calculate ROI
Training Video by
Mike Turco
Learn the 7 Quality Control
Tools Video by Gemba Academy
How to Upgrade to
SigmaXL Video by
SigmaXL Inc.