hermies are not always the end of the world. no one wants them but they dont spell disaster every time. they can happen for a ton of reasons some easy to explain some not so much.
the drawback is seeds obviously but the process of making seeds takes energy away from producing more potent trichomes. it can still be killer herb and the plus there is, the seeds will be more inclined to produce females since it was a female pollinating itself.
probably best if you do find a plant with a hermie, whether its one or dozen, is isolate it so it doesnt contaminate more plants or your flowering area in general.