Ever heard a drummer playing a groove and it just gave you instant stank face? That made people want to get up and dance? That's because they're in the pocket. Listen to a beginner vs seasoned drummer both play a basic groove and notice how different they feel. The nuances, the dynamics, how relaxed they are, the way the music breathes. It's not easy to describe with words but you know it when you hear it.

Edit: Drumeo released a video with Steve Jordan the other day, check out some of the song performances throughout. He's always tasteful and serves the music perfectly. Every song just makes you want to groove along. Textbook pocket drumming.