At which point you've already wasted $10,000 of someone else's money. There's also the good ol' sunk cost fallacy. The longer you've spent working on your dumb

At which point you've already wasted $10,000 of someone else's money. There's also the good ol' sunk cost fallacy. The longer you've spent working on your dumb business plan, the less likely you are to change it to a smart business plan.