Hate’s a pretty strong word. I think it’s the worst of the three Star Wars films (there are only three), but I still enjoy it enough. Here’s where it falls down:

Unfunny funny bits: Comic droid torture, various Ewok slapstick, Chewie gives a Tarzan yell. These are the little excesses that, in earlier years, may have been pruned out, back when Lucas listened to criticism. Humor is good, but good humor is better.
Nobody has much to do except Luke, the Emperor, and Vader. Han is pretty useless, Leia stops being useful when the disguise comes off.
Nobody has uncertain loyalties. Han and Lando both wear white hats from the beginning. No scoundrels. Yawn.
Some people think the second Death Star is a cop-out. I didn’t mind so much.
Cute Ewoks. For me, it’s not so much that the Ewoks are cute per se, so much as that cuteness is really played up. The “roasting on a spit” sight gag was already so stale in 1983 that the audience knew there was never any menace (note that for younger folks, the “roasting on a spit/boiling in a kettle” trope might not be as thoroughly familiar as it was to audiences at the time).
Lots of exposition. Sure, it starts with a big action scene in Jabba’s palace, but quite a lot of the scenes are just people standing and talking. Luke and Yoda, Luke and Ben, Luke and Leia, Luke and Darth, even Luke and the Emperor a bit.

That said, it brings some good things to the table, IMO:

Great designs, scenery, effects. Sure, the Rancor looks a bit like a bluescreen menace, but Jabba’s palace in general, the the space battle were both great.
The score is still solid. I actually don’t care for the Ewok theme (talk about playing up cutesy), and the Yub Nub song and Lapti Nek only look good compared to what they were replaced with, but the rest is very solid. John Williams hadn’t hit his decline just yet IMO.
Even though the plot was overly focused on Luke’s journey IMO, Luke and the Emperor both are very engaging, and deliver with strong performances.
It closes the Star Wars story. While Empire followed more of an episodic cliffhanger path, this film clearly resolves things. I’m satisfied with a Star Wars saga comprised of three films, and feel no need for more.