Not an expert, but I imagine for anything bigger than a home business you have lots of the same overheads, you don't pay for a shop but you pay more for virtual shopfront stuff. You can't just put everything on ice and have no outgoings, you still need cash flow.
I've tried to think of a way to ask this without it sounding critical, it's not meant to be:
How does an internet shop go bust?
Buying stock on tick in the hope it'll sell on before you have to pay for it?