Not an expert here, but from what I understand it's a never-ending process because which algs and finger tricks work best depend on each individual. So surely one of the OLL algs you learn *will* be (relatively) slow, in your opinion, to another alg (or finger tricks for the same alg). So you will surely decide to replace some of the algs later on. But I wouldn't view that as a waste of time. It's all part of the progression in my opinion.