Ratmansky would never stay in one spot with one company for monetary reasons and for artistic reasons - the reasons that motivate dancers. Don't forget that NYCB offered Ratmansky a choreographer in residence position, but he turned it down because it was too restrictive and required him to spend too much time at NYCB. (The gobs of money that Ratmansky is making by selling his talent around the globe was never specifically mentioned as a reason for turning down the NYCB job, but it seems obvious that was part of the motive.)
The "gobs of money" motivation doesn't seem obvious to me. He could make a lot more by not having a long-term contract with ABT and not having to be based in one of the most expensive cities in the world, where being given prime real estate is not part of the deal.
Ratmansky reminds me much more of Jerome Robbins, with an anchor to one company, in Ratmansky's case ABT, but with enough freedom to take on projects elsewhere. Ratmansky's projects are ballet-focused, unlike all of Robbins', but he gets to work with great artists and decide whether he likes the conditions and the atmosphere before doing more work with them. He gets to experiment and then to cherry pick.
if memory serves, NYCB did not, finally, extend the offer because it wasn't ready to have him in the position vacated by Wheeldon as he kept commitments to commissions to various other companies for new ballets in the works at that time.
I think, though, if both sides wanted to work it out, the appointment could have been delayed for a couple of years so that Ratmansky could have fulfilled his commitments and cleared his calendar.