I can understand tracking metrics for performance (as in speed, server load) or revenue. But I don't see how anyone could make such conclusions as they did with a straight face, apart from achieving some OKR for promotion reasons. There's no substitute for user research, focused mindset and good taste.

I can imagine that's why today's apps suck so much as most of the pain points won't be easily caught by user behavior metrics.

One thing Alex from Organic Maps taught me is how important it is to just listen to your users. Many of the UX improvements were driven by addressing complaints from e-mail feedback.