It's easy to forget that depression isn't rational. A depressed person may worry that they're unhirable and won't be able to find a job in those 4-6 months. They may expect that any job they do find will be as bad as the current one, or worse. If they're on a visa, they may worry about deportation and having to upend their lives if they leave their current job. They may worry that a gap on their resume will affect their career prospects. They may worry that their friends and family will judge them if they're unemployed for a while. Etcetera ad infinitum.