In 1996 the Charlotte Hornets drafted a 17 y/o Kobe Bryant, then traded him for Vlade Divac. Divac spent two years in Charlotte and then left for Sacramento as a free agent and was a big part of their Greatest Show on Court years. So Charlotte drafted a generational talent and traded him for a guy who would leave in 1998 and have a better career elsewhere, ouch.
Six years later, the Hornets left Charlotte and while they came back in the form of expansion, the new franchise has never won anything.