Sure, it is completely reasonable to stay in a well paying job to avoid the risk of losing money (and sanity since if you only make the same money in your own business you'll likely be much more stressed.) To be clear, I'm not criticizing anyone who makes that choice. I made that choice for a long time since I have a family to support. But I didn't make fun of entrepreneurs who weren't trying to boil the ocean. I've always found those who do that a source of amusement.