The fewer customers one has the less money it costs to pivot. A lot of tiny companies pivot like crazy with very low cash flow.

No, they require time.

But time is money.

And I am not trying to be cute here. It is properly the single most common tradeoff here - you sell your hours for pay at a company, then buy a frozen pizza because you don't want to make it at home, then clean your own house because a maid is too expensive but outsource your taxes because they are so complex and would take you ten times longer to do, you drive a car because commuting by bike is too slow and the buses don't come by that often.

Time can be brought (heck that is kinda what you are doing with your start-up because a successful start-up can mean you don't have to work at a job again, ever).

The difference between time and money is that you have time by default. I assume most entrepreneurs started to work on their business in their spare time before having the money to quit and work on it full time.