Or, hummingbirds vs. stinging insects.
I built your basic wasp trap. They and the yellow jackets that plague the HBs show much interest, but they aren’t stupid enough to go into the trap.
My bait is sugar water with detergent in it to kill them.
What am I doing wrong?
Yellow jackets are carnivores. Try putting some meat in there.
I would think that sugar water just doesn’t smell enough for them to find it. Put something sweet smelling in it, like soda or wine or beer. Or maybe just some vinegar
Good idea.
Did catch a wasp today, though. 
I saw, on another board, where a guy was plagued by wasps. He hung a plastic bag up that slightly resembled a hornet nest. Hornets dominate wasps. Wasps went elsewhere.