I'm a poker noob and I need something explained to me. How come it "feels" like flush draws have a much a better chance than open-ended straight draws even though there's only a difference of 1 out?

Is there something I'm misunderstanding? Only counting the draw and nothing else, a flush draw gives you 9 outs and an open-ended straight draw gives you 8 outs, right? Is it just in my head that it feels like flush draws hit more often?