1-I would guess that a back-up plan (even if it’s, If I fail, I can always wait tables for six months until I’m in a position to try to execute a new idea or build a new business) actually HELPS a lot of people make the leap to become an entrepreneur, because they know it’s not the end of the world if their plan fails (which is different than being unfocused or not obsessed with making it work).
2-You hear the trope about failure being necessary to success all the time. So, doesn’t the fact that failure is a part of the process also mean that a back-up plan (i.e. the next business you try to start after the previous one inevitably fails) is inherently built into that process as well?
Like any other piece of advice, it sounds sort of call to “burn your back-up plan,” but it totally depends on the context.