I'm not 100% sure what that statement is referring to I can think of many things it might be talking about. Monetarily it could mean you started with zero maybe gained a little but in the end you ended with zero. Essentially you had no gain or loss. It also could mean the makeup of a person their character when they have a zero personality, or lack socializing skills. You could mean a person feels like a zero even when they're not because of circumstances like being overlooked, not being recognized Etc ???
Nope. One other reference might be a career choice or job. Stuck in one place, not succeeding or promoted.
Maybe it means you're not making any progress. For me just getting up in the morning and getting dressed is progress.
Tell me about it! It is easier to wash my dogs now than myself. Buying a back brush helps me not injury shoulders washing my back.