What is a phrase for being stuck at a job because of unwillingness to take a risk?

As a sample sentence

I realize that I have <insert phrase> for too long. I need to quit this job and take my chances.

There is a modern expression "comfort zone" so you could say "I realise I have been stuck in my comfort zone for too long".

To tread water is literally to swim in place moving your legs and not going anywhere. But it has a common figurative meaning: as Collins Cobuild says, "If you say that someone is treading water, you mean that they are in an unsatisfactory situation where they are not progressing, but are just continuing doing the same things."

It captures the idea of repetition, lack of progress, just trying to keep alive without doing anything better. If you're literally treading water you're probably waiting for someone to throw you a line or a flotation device, and similarly in the figurative sense you're not taking control, you're just waiting to be rescued.

You would say: "I realize that I have been treading water for too long. I need to quit this job and take my chances."