The people I know who buy larger (say 55' +) boats, (avid fishermen, and YC members who have waited years for the seniority required for a larger boat, in both cases, having owned successively larger boats for years) are probably not representative of the typical buyer in that category (I can't even imagine who else is buyer larger boats, especially those not requiring a full time crew), but the people I know hold on to their boats for many years. And, although I know only a few of the other owners, my boat's sisterships come to market rarely, usually because of the death of an owner, though in one case, at least, the decision was a financial necessity.