"Death by a thousand cuts" doesn't show up in a spreadsheet because each cut is hidden in a different cell.

We've all worked in the industry long enough. We know that if you approach the PM and say, "man, I watched my girlfriend try to use the site on her phone this weekend. She gave up because every page tried forcing her to use the app," the PM would respond, "we did some testing and not many people stop using the site when this happens, and people who use the app are 3x more engaged, so this isn't true in practice." But those tests don't show what happens 3 months from now when your girlfriend uses a competitor that doesn't have any of that shit, and she thinks "wow this is so much better" and just never goes back.