My favorite is the first one, "The best engineers are obsessed with solving user problems." and what I hate about it is that it is super hard to judge someone's skills about it without really working with him/her for a very long time. It is super easier said than done. And it is super hard to prove and sell when everybody is looking for easily assessable skills.

This is why (flawed though the process may be in other ways), a company like Amazon asks "customer obsession" questions in engineering interviews. To gather data about whether the candidate appreciates this point about needing to understand user problems, and also what steps the candidate takes to try and learn the users' POV or walk a mile in their shoes so to speak.

Of course interview processes can be gamed, and signal to noise ratio deserves skepticism, so nothing is perfect, but the core principle of WHY that exists as part of the interview process (at Amazon and many many other companies too) is exactly for the same reason you say it's your "favorite".

Also IIRC, there was some internal research done in the late 2010s or so, that out of the hiring assessment data gathered across thousands of interviews, the single best predictor of positive on-the-job performance for software engineers, was NOT how well candidates did on coding rounds or system design but rather how well they did at the Customer Obsession round.