I would say, for example, that a job interview helps provide a vibe for the current situation at a company. But it's not a perfect signal, and as an individual I can't go on that many interviews. Hence looking for other approaches people have tried.
> Companies tend to optimize for profit, not for the comfort of programmers.
I believe that's a separate issue from my question. Seeking profit doesn't force a company to hire incompetent or apathetic programmers. If anything it wastes money on salaries that don't deliver as many new product features to sell, or as many improvements that will increase customer retention.