One player really stands out regarding this point. When Beckford was playing for Leeds in the championship, he was scoring a lot of goals, and several premiership clubs were interested, and his value was high. Everton got him, and he was a total flop so his worth plummeted as he couldn't play as well at the higher level.

We will have to wait and see as regards Zaha. He is as yet, unproven against International class defences.