In my headcanon, the Predators we see in the movies are just the uber-macho ultra-violent toxic-culture types who are hyper-fixated on hunting. It would be one thing if a human defeated a Predator once. But the number of times we've succeded? It's because we're not really seeing the best-of-the-best. We're seeing the Walter Palmer types to pay to go on safari and shoot a trapped lion.
We've never seen the Predator homeworld (in a movie). I want to see the day we first travel there and land in front of huge monolith, only to discover it's basically a giant office building. We are warmly greeted by a Predator secretary, and when we start talking about our first encounter with a Predator the secretary is like "Oh, jeez. Are you talking about Steve? Yeah, we all hated that guy. Never shut up about his tacti-cool toys. Actually, when we heard about that we started a petition to protect your planet as a wildlife preserve until you acheived space flight."