Remember that the Launch League are a mixture of experienced and dedicated managers and new folks just checking it out. They serve to weed out managers who would be unable or lacking the interest to handle a full season team. Perhaps when the see how the draft takes some work, they feel overwhelmed or just lose interest. It's a free trial so there's nothing to lose. I experienced the same thing in my launch last year. The "real" leagues, if mine is any indication, are much better.