Ask HN: Why do analytics tools show what happened but not why?

I've been experimenting with analyzing websites from a behavioral perspective instead of just traditional analytics.

One thing that keeps standing out is that most analytics tools tell you what happened (bounce rate, session time, funnels, etc.), but they rarely explain why visitors behaved that way.

For example, a high bounce rate might mean: - confusion about the product - lack of trust - unclear value proposition - hesitation about pricing

But the analytics alone usually don't reveal which one it is.

I'm curious how other builders here approach this problem.

When you look at your own product or landing page metrics, how do you actually determine why users hesitate or leave?