According to standard economic theory though, the fact that someone says "I'm worth $X to them" is completely irrelevant and, because the transaction never happened, never becomes data. That's how market rate is determined and generally why D/S curves only have 1 intersection point - the point at which the transaction occurs.

The only data point that matters is the one where you got hired and started receiving paychecks, all others are not factors at all.

> According to standard economic theory though, the fact that someone says "I'm worth $X to them" is completely irrelevant and, because the transaction never happened, never becomes data.

I don't understand that. If an employer offers $X, I'd say that means the applicant was worth at least that much to the employer, assuming the job offer was legitimate. I suspect it's fairly rare to get an offer for $X, only to find out that the employer was lying and won't actually pay that much.

I have seen quite a few employers and some of them are noticeably much better at converting developer work into revenues than others. Those companies are able to offer higher salaries even to worse developers, simply because they can make more money on every quality-equivalent unit of work.

The $Y amount may be higher than $X because you are actually worth $Z to a median company, and $Y > $Z because that particular company is in the 90th percentile at turning developer work into revenues, and $Z > $X because that company is in the 20th percentile.

So, generalizing, the company that is capable of offering the most to you is going to be better at managing development teams, which is usually a symptom of being a better employer overall.