hpux

They are some unspoken rules in the industry that no one explains to you when you start a job. Knowing them could kickstart your career and put you on the path to success. Top performers on every team usually do these things, but they don’t realize their importance in their success.

I don't necessarily agree with your observation. The issue here is that companies like Facebook hire a ton of entry-level (E3) engineers each year that come from their intern pool. Although many of them get promoted, not everyone can pass the bar. The need for more senior engineers is persistent in the company. Another thing to mention is that typically there is no headcount for E3 engineers at Facebook (besides returning interns) for external hires.

On your second point, that's the reality for many established tech companies. I know many solid senior engineers that can't pass the entrance bar to FANG. That doesn't mean that they are "bad" engineers. Overall I think you can replace Facebook with Google/Apple/Microsoft/Netflix/... in the blog post and the end result would be the same.