We had a big discussion of this in our Sunday School class, much to the dismay of the priest. I have always wondered about it myself. It's not religion-bashing to wonder why God sends tribulation on people and certainly hard to imagine that He does it because he made a bet with Satan about where your breaking point might be! Anybody have any answers they have actually thought about, besides knee-jerk ad hominem attacks?
The information gained during the cleansing-trial times isn't for God's benefit. It is for our own. We gain insight into how finite we are, how much we depend upon God and what His vast resources are.