musical jobs
When I was a computer programmer, the common way to get a raise was to go from company A to company B. Then company A would hire someone from company B, where you had just got a job and a raise, to replace you. The new hire would get a raise over your salary that was much more than you asked for to stay. It was all insane.
Then of course, each company had to waste time and money training you and getting you up to speed. I Never figured out why they acted so irrationally.