What an incredibly relevant example, David! I think our jobs are the easiest place for us to get complacent and settle when we could be doing so much more by moving on.
I’ve heard that the 3-year rule works rather well for this: Never stay at the same job for more than 3 years. If it’s a really good job and you’re still learning, 5 years is acceptable, but beyond that it will only serve to hold you back.
It’s never too late to put on those shoes and start climbing. 🙂