It's actually a normal and proper way to improve usability if done right, i.e. in a study where you set tasks to users and watch what they're doing and where th

It's actually a normal and proper way to improve usability if done right, i.e. in a study where you set tasks to users and watch what they're doing and where they have problems. Jakob Nielsen does this for decades. Not sure if looking at users' screenshots is anywhere near as useful.