There's a few players who have been sold for decent fees that have done nothing with their careers - James Scott going for £1.75 million is the most obvious example..
Equally there's a plethora of guys have we've picked up from the wilderness and sold on for significant money - Kipre & Bair being the two most best examples of that recently.
As much as plenty of people like to complain, Motherwell's player trading over the last decade+ has been a roaring success.