The worst two off the top of my head is Isiah Thomas and Kevin Mchale. Isiah Thomas just messed up that New York team with too many stupid decisions. It's crazy because they have the highest payroll for a team in the nba but Isiah keeps getting players that dont fit too well with each other. Kevin Mchale, well he just wasted a Kevin Garnett's career. He hasnt put anyone beside Garnett and for that sole reason they havent made the playoffs for a few years. You gotta feel bad for Garnett, a passionate player who deserves a ring but isnt getting the proper help from team management.