In order for that to happen without repeating artists, I'll have to keep being introduced to new music. That's pretty cool. I find that sometimes you have to set a goal with the intent for it to generate secondary effects. For instance it seems easier to try to keep doing the pick of the week thing which forces me to try to find new music than to just look for new music for the sake of finding it.
I think that kind of thing can help people stay in shape...if you want to get in shape, sign up for a race. That way the race will push you to train for it. Otherwise there's no carrot/stick to your plan to get fit. School kinda does the same thing. The goal is to learn, but they make you take tests along the way as a means of keeping you on track. I like to keep my car running smoothly, but it's probably the threat of breaking down on the highway that actually keeps the maintenance at a higher level.
Do you do stuff like that? Set one goal in order to achieve another?