I agree with the random treats.

The analogy I like the best is one that compares it to gambling.

Say you're playing a slot machine. You put your quarter in and pull the lever and jackpot. You put your quarter in, pull the lever and nothing. Put the quarter in, pull the lever nothing. Put the quarter in pull the lever, jackpot. You keep putting in quarters because you remember that sometimes you do get your jackpot. And although most times you don't, you will always remember the time you did.

Hope that made sense....LOL