>>472989801. It is good in OU. It had a great performance in a tournament and the ladder has just recently caught up. If May was a tier shifting month, it would be OU now.
2. It's extremely good in UU, being the most used mon in the tier.
3. Even if it wasn't good in UU, that wouldn't preclude it from being good in OU. See mons like Ditto and Shuckle, who would be Uber if it was a usage based tier, but are actually Untiered because they can't even keep up in PU.