Everything is cyclical, but the Eastern Conference has gotten extremely unlucky with the lottery when it counted the most. When there's been that exceptionally rare "can't miss" prospect, the West has gotten the better of that deal. When I consider those select handful of guys who were really known as being the "next great thing", I remember only a handful of guys who had that reputation. And the West has gotten most of them from the past 15 or so years:
West: Tim Duncan, Yao Ming, Carmelo Anthony, Greg Oden, Kevin Durant, Anthony Davis
East: Lebron, Elton Brand, Derrick Rose
In many of those, the West leapfrogged an East team to get that true blue-chip player (Duncan, Durant, Davis) whereas the East's only leapfrog in that list is Elton Brand (and I'm probably being generous including him on this list). And 'Melo was a gift-wrapped present from Detroit to Denver.
Now maybe my memory is faulty. Maybe this is just selection bias. Maybe there were some other guys who were tabbed as "can't miss" in that time frame. But I can't remember any. I remember plenty of really good basketball players like Dwight Howard, but even he wasn't pegged as the next sure thing.
I'm not suggesting a conspiracy or anything, but face it - the East has generally gotten Edited. Profanity and masked profanity are against forum rules and may result in discipline. on in the lottery whereas the West has leapfrogged East teams at the most opportune times. That's one reason for the imbalance.