There are a few different ways to spin that metaphor, and here's mine. After you achieve a certain level of success and comfort in your life, there's a real reluctance to do anything to rock the boat. The more you have, the more you have to lose. The more risk-averse you become.
I'm guilty of lingering at the Mediocre Inn. While I hope my work hasn't been mediocre, I know my life has been. It's been comfortable. Easy -- not to say I haven't worked hard, because, God!, how I've toiled -- but easy in the sense of predictable. I've been living in a controlled environment where everything I do has a moderate range of expected outcomes. No sudden moves and no big surprises.
Until I finished law school, I'd spent the whole of my life in one little corner of Pennsylvania. Then I astonished everyone by accepting a job in Alaska even though I didn't know a soul there except the people who'd hired me. But I was single, mostly broke, and I'd always dreamed about life on the last frontier. Now or never, I thought, and off I went. It was a Bold Move, but I had so little to lose back then.
Now I'm on the brink of another Bold Move, and I have a few things to lose this time. A comfortable niche in the legal world, the warm regard of clients and colleagues, good friendships that will inevitably fade with distance and diminished opportunity. But there are new adventures out there, and I'll never experience them if I don't put down my mug of hot chocolate and get up and out of the Mediocre Inn. The summit is still up there, and I still haven't scaled it.