People who average like 1000+ scrobbles a week. Just no. Turn it off when you're not listening.
Not being able to fix the album tag. Like when you listen to the first single 200 times and the album name is released later, there's no way to put the scrobbles under that album. It makes me just not care about album tags which makes it even more of a mess.
Not being able to see the most scrobbled artist/track of a certain period. You only have the past week, past month, etc. filters and the charts per week.