I have a different theory. You keep them simple and cheap(made from scraps). When you are done you dismantle them and save the reusable pieces. Chances are when you need it again the size, angle, registration capabilities, etcetera, etcetera will not be similar enough to use it anyway. And then there's the fact that you will have figured out a way to build it better by the time you need it again. There are only a couple of exceptions. Crosscut sled for table saw, grooving/dado jig for router for example. Don't waste valuable space with jigs it may be years before you use them again.
Someone I consider a master woodworker once told me that a master woodworker is not someone who never makes mistakes. He is someone who is able to cover them up so that no one can tell.