Some possibilities:
- Because she's loyal to her co-workers
- Maybe still not jaded enough to jump ship at the first reason
- quite possibly didn't have another job lined up to jump ship to
A year isn't all that long, and if things had been turned around who knows she might still be working there today. Obviously they have not, things have gone rapidly downhill so she made the right choice in abandoning Uber but you really can't fault someone for trying to fix things before they give up.