Here’s the letter I wrote
I’m done with this job, I hope you find someone who can put up with the wide variety of trivial personal preferences that each editor seems to have. One day an article isn’t focused enough, one day it is too focused. (name of company) is great, the ever-changing whims of the editors, combined with stricter standards that I think they’ve all interpreted differently is ridiculous. I’d like to leave on good terms, I think the company is fantastic.