Especially in a mobile-first world, fast loading websites are of utmost importance. Also, Google has been very vocal about anything web performance in the last few years and is pushing hard to innovate repeatedly. But performance is so much more! User satisfaction should be the main goal because expectations are clear: You’ve got two to three seconds maximum to deliver, so make it count. During Bastian's SearchLeeds 2018 talk he walked through various advanced topics around web performance optimisation going way beyond Accelerated Mobile Pages (and other short-term solutions) to make any website really, really fast.