Context is important though. For instance, developers applying for management position with no management experience. In other words just because they work at a company does not mean they are qualified for the position there (or elsewhere). Those people would likely quit out of resentment.
I think in many cases people think they deserve a promotion based on seniority—but they don’t show signs of going above-and-beyond. Simply working somewhere longer does NOT warrant any merit increase in my mind. Doing extra things to help the company in ways beyond ones role deserves merit increase/promotion.
I’d argue more times than not, folks consider time-spent on the job a sole factor in guaranteeing that promotion.
For instance, someone new might join a company and have a skill set above and beyond folks who have 2+ years of seniority. That new employee might demonstrate exceeding merit in two months of employment—and in my mind, the new hire should get the promotion.
Granted, that’s comparing two employees who work at a company already. I suppose in the interview process it would be based on fact (existing employee) versus word of reference and how well the new hire sells their abilities.
And that’s why I’m not in management because I’d rather not have to deal with making those decisions!