Being self employed doesnt automatically means that we would really be having that job forever which there's still a certain risk that you might able to lose that job and if you dont make yourself other
back up investment or businesses then your fucked since there are no other source of income you do have unless if you do get some job directly after you've been fired or laid off.
There's no assurance or guarantees on this world even on dealing with those typical things.This is why it would be more wise and sensible if you do always set out Plan B or Plan C and so on....
Sometime business fail and the only option we are left with is going back to our job.
I my case - none of my business plan succeeded - maybe I am too poor at planning or maybe I am to unlucky to start my own business.
I ended up applying for the jobs again - what a poor entrepreneur me!
Yes business do fail which is why we need to keep building our businesses to get to a level where we can be rest assured that everything is okay. I will always prefer doing business that going for an office job which you could be fired anytime. You work for your boss and resume work whenever he wants you to resume. Your time becomes you Boss time and he will pay you about 1% of what you are making for him.