What are some examples where the "Harder Boss = Better Boss" trend is NOT true for you?

For a lot of cases, the harder a boss, the better the community tends to rate it. Most likely due to emotional payoff for overcoming a challenge. What are examples of Bosses that defy this trend?

What are Bosses that are not as hard as others in the series, but you still rate them higher than the more difficult bosses (due to other things like aesthetic or music)?