Should there be a restriction on fighters coming back from retirement?

It's happened before where a fighter announces that they will 'retire' from boxing, only to come back into the ring after a couple of years. SRL, George Foreman have done that before. Just recently Sergio Martinez is planning on fighting again once more and will finalize an opponent, date, and location in a few days. And then you have Chris Eubank and Nigel Benn wanting to go at it again after decades out of boxing.

My question is should a fighter not be allowed to ever come back into the ring once they retire from the sport for good? Do you think that they should enforce a restriction against fighters, who have announced retirement, to box again.