Catan and King of Tokyo. Catan was I think the first "modern" board game I was introduced to and it did not click at all. King of Tokyo wasn't awful but given how popular it was at the time, I was expecting more. I've only played them once, to be fair, so it's a bit hard to get into details but they're the 2 that come to mind!
I also do not like Catan. Tired of getting pigeon holed in resources and then having to convince another player to trade when I have no real bargaining power.
Catan just feels weird. The thing is - and I kinda validated that recently by watching highlevel competetive play of the catan base game, but: You only have like 2-4 meaningful decisions in a game. The rest is just follow through and dice.
And these things aren't that hard to see at a decent level. And when you make these decent decisions, you mostly just win. Even with the robber, there's limited counterplay to these good initial choices. This makes it hard to play casually as well once you know the good things.