I kinda had that same feeling at my last gig (some 20 years ago...).
It took a RIF and getting let go for me to finally launch my business (still going strong). I remember one of the more friendly directors came to my office when I was packing up my things and said "_______, what are you going to do?"
And I remember my reply as if it were yesterday "Linda, I have been thinking of doing something else, somewhere else, for quite some time now. I'll be fine"
So to answer your question: When you are in a position to smoothly transition. Generally, that occurs when you are financially ready to turn the page to the next chapter.
