One thing I think people discount about this is the subconscious cost/benefit analysis. When something is an interesting puzzle to solve, the benefit is really high and the cost of a POC version is really low. Once it comes time to turn that POC into a workable product the cost/benefit changes. It loses all the value it had for being interesting and the cost shoots way up. It's easier to not have this problem when the lost value is replaced by money.