This makes all the sense in the world

Lol. Well said. But even then- the particular confident person it still doesn’t work- because their assumption will almost always be that a person likes them. Even relying on others- saying: “if other people can tell they like you...” isn’t perfect. And even more so when you’re young- as love can be particularly confusing when people are just experiencing it and have t really figured out what it means to them or sometimes who they even are. I’d say... if you ask them out and they say yes, and then you “make a move” and they go with it, and then you say you love them, ask them to move in, marry you, have a baby... and they go with it- I think they like you.