Four ways to keep your lead scoring model updated and relevant are: 1) Allow input from sales by letting sales recycle leads back to marketing and enter their own scores to compare with marketing's scores. 2) Track scores at inflection points like the average scores of opportunities that became deals. 3) Review the lead scoring model every quarter and make updates based on sales feedback, traits of new customers, and changes in the market. 4) Test new things like predictive models and track score changes.