Earlier quoted context omitted.
This is the risk with at-will employment in CA. The employer could very well decide after two days of you working there that they wanted to let you go -- there's no part of the contract keeping either side from ending things early. I don't think it's unethical to leave after a short amount of time given the employer has no equivalent expectation.
A buddy of mine got a new job, quit the old one, showed up day one and was laid off immediately. Apparently their budget had changed. Oof! We also hired a c-level exec who came aboard apparently having already accepted a different offer and came on for under a month to collect pay and get some juicy stock. Apparently they negotiated well and walked off very, very well paid. Edit: not sure if I have a point there othe…
They talked about making him full-time. Negotiated an offer, relocation package, etc., all good. He set about selling his home, finding his kids new schools, etc. And then about a week before his start date, he got a phone call.
"The clinic has been sold to new owners. They are reviewing finances and rescinded any job offers, including yours. They will allow you 30 days to repay your relocation assistance."
Oh hell no. He lawyered up. He'd sold his home. Had a whole bunch of language in the employment contract that the new owners were unaware of, to ensure things went "smoothly".
He didn't end up repaying his relocation assistance. And his "new" "employer" ended up paying three months salary and the closing costs on his house for the inconvenience.