There is no such thing as luck. Probability by definition takes into account that things won't always happen as they *should*. Over the long term though, probability = reality. If you have the proper pot odds to continue a hand in any scenario in a cash game, you should always call. This takes assumes that the actual immediate results of winning / losing don't matter to you, which they shouldn't. Otherwise, you're just playing scared.

I agree with whoever said they'd call 8 days a week.