Unless it's some one off batch process or a prototype, if the codebase doesn't last at least six months then it's unlikely to be something that makes any money.

Unless it's some one off batch process or a prototype, if the codebase doesn't last at least six months then it's unlikely to be something that makes any money. In my experience, badly designed code tends to become a net loss after a couple of months because after that time someone is going to have to modify or fix it.