Sometimes, players do great things, retire, and go on to be inducted into the Hall of Fame. See Chris Chelios, Scott Niedermayer, Brendan Shanahan, and Geraldine Heaney. Other players do nothing, make money, and "retire" at 30. See Ilya Kovalchuk.
Only 3 seasons into his billion year contract (okay okay fine 15 years), Kovalchuk has announced his retirement, leaving $77 million on the table to return home to Russia.