Musicians give up for a variety of reasons. There are plenty of people out there who can't handle the pressure; as we've discussed earlier, this industry can be pretty cutthroat at times. Music is highly competitive - not just in getting your music heard but also in making money from it. Some musician's circumstances change having a family, so they need to focus on more stability and guarantees to pay the bills. Probably one of the saddest reasons someone might quit is when they lose their passion and fall out of love with music.