Because even a 7-footer with no game can be a servicable player. It reminds me of a Mitch Hedburg joke in an abstract way. "Escalators can't break. They can only become stars. When they break, they should put up signs that say 'sorry for the convenience.'" Just like highly-touted 7-footers going into the NBA. They may suck, but they're still taller than 90% of the league.