How did you find out your friend is dumb?

I’ll go first. My friend, Bill and a few others went to our local amusement park to get on the new ride. When Bill was getting strapped into the seat the ride operator started talking to him and they were talking about their day. After the ride they got back in line and the same girl started talking to him again. She told him, “Hey you should come back here later so we can talk some more”. My bro did NOT ask for a phone number, snap, insta, nothing. I got there like an hour or so after this happened and he never realized until I told him. So I dragged him back to the ride and she was gone. FUMBLE OF THE CENTURY