Jokes aside, maybe he over-hyped it. Maybe he expected, from the way people act in movies and porn, that him touching a breast would bring him sexual pleasure? Or maybe she wasn't into it? Maybe she was just like: "... Yyeeaaah, okay. Go ahead, I guess. I'm just gonna be on my phone, checking my messages.", and so he didn't get the thrill of bringing her pleasure from a simple squeeze?

... Or maybe he failed the test and doesn't actually feel things. Maybe he just takes appropriate actions based on outside input he's received and so assumed the pinnacle of his life would be the booby? Dunno.