Thinking Aloud
I get approached to do a wide range of projects. More often than not they turn out to be not terribly well-thought out.
Sometimes by the time I have finished the project proposal (sometimes it is a fully working prototype like this one), the commissioner realises they don't have something important, maybe it is the money or the support of their trustees or a permission or perhaps the imagination or the money or someone else says they will do for nothing and it doesn't happen.
But sometimes I get paid a silly amount of money. In these cases the project lands on time. Sometimes this means that they get what they are given. If deadlines matter don't be too picky. If on the other hand you don't mind a project arriving years after the foal has bolted, make sure you have an unlimited budget and have an army of willing volunteers with nothing else to do.