At a past company, we originally had a fairly flat org structure. Jr, Mid, Sr, for the ICs. It worked, and everyone was happy. Eventually they brought in some new leadership from one of the big tech companies, and the new leadership brought a levels system. Suddenly we went from a large and flat org, to having all sorts of letters and numbers for levels. And none of the existing staff was promoted to the new levels, they just got moved to the equivalent, while the new leadership hired their own people to the higher eschelons. This already damaged morale, because you had new E6 and E7 or whatever engineers who didn't know their way around the codebase at all, while an E2 or E3 was having to do everything.

Eventually they promoted a few of the original engineering staff. I was told during one of these promotions cycles that I just barely missed the promotion targets. I asked for concrete metrics of what I could improve on, and was given a few vague and nebulous answers. I worked on these, even though they lacked definition. Come the next promotion cycle, I was, once again, passed up. When asked for clarification, I received more vague, nebulous answers. I was assured that I was going to get it the next round, and they'd be doing promotion cycles more than annually.

They kind of kept their word: promotions cycles started happening every 6 months. But the next cycle came through, and once again I was left behind. So this time, instead of asking for clarification, I just started looking for a new job, and handed in a letter of resignation a few weeks later. Upon handing in the letter, I was told "oh we were going to promote you next week!"

I wasn't born yesterday, so I told them thanks but no thanks.