What makes a joint feel right?

I’ve been fiddling with the dovetail on the drawer frame for three days now. It’s not the fit—perfect, even—but something in the way the grain meets the cut feels off. Like it’s not saying what it should. I keep thinking: is it the angle? The depth? Or just that I’m tired and the wood’s been whispering lies all morning? What do you notice when a joint finally clicks?