Every? Are you sure? What if the coach changes? What if the player has personal problems and can't settle? What if the tactical setup of the team changes? What if he gets injured? What if another players develops better and he can't get in the team?
Besides, it's not as if 70% of Udinese's signings aren't failures anyway. That's what they do, scattergun it, give them all a go, sell the best ones for 300% profit, do it again. As we want to actually win things we can't do that.