"Life is a gamble," Mother Cabbage told her offspring, Brussels Sprout. "You have to weather storms and drought. You have to fend off animals, bugs, mold, and rot. But if you hang in there, you'll grow."

"I'll try," said the little Sprout. "But how long does this take. When should I stop growing?" 

"As with any other gamble," said Mother Cabbage, "quit when you're a head."