Earlier quoted context omitted.
> Sure, you can spend the weeks to months of expensive and time consuming work it takes to get a fuzzy, half accurate and biased picture of what your users workflows look like through user interviews and surveys. Or you can look at the analytics, which tell you everything you need to know immediately, always up to date, with perfect precision. Yes, admittedly, the first time you do these things, they're difficult, ha…
Asking users isn't a substitute for usage data. Usage data is the ground truth. Soliciting user feedback is invasive, and it's only possible for some questions. The HN response to this is "too bad" but it's a thought-terminating response.
For what, precisely? As far as I know, you can use it to know "how much is X used" but not more than that, and it's not a "ground truth" for anything besides that.