Flawed comparisons, because of all of those legal occupations, only traders can go negative on a day's pay. They (the folks with regularly-paying jobs) are paid by the people they work for, for their efforts. On most days, they do their job and they are paid a sum.
The next day they are not then asked to give back their hard-earned money.
Only RL career I can see trading being comparable to is one with a draw vs. commission schedule. Or salary + commission with draw. You get the idea there.
So "regular-paying-jobs" means daily profits for the company writing the check? WOW!
What is flawed is you thinking a trader is different than a "regular-job". A string of bad days trading is no different than a string of no-widgets-moved days. Or losing a bid to clean the 20 story office building. Or having many small accounts, or maybe your largest account, 90+ days in arrears. or, or, or.
If a trader removes 100% of daily gains, or removes nothing, as in all or nothing, that trader is not operating as a business. Either his income is too high relative to his account, or he is just a hopeful, wide-eyed child wishful thinking his "business" will be sustainably successful. Yes it can happen that way, and for some, failure is not an option works well. But for many, perhaps a "regular-paying-job", whether the company is profitable each and every day is irrelevant just so long as the check clears, and saving a few bucks to be used as working capital rather than rent might be more suitable or appropriate.