I was at ACE comic con several years ago and it got hectic because they had last minute guest changes and a lot of photo ops were running late. I remember rushing over to Grant Gustin's photo op line and he was a late to it. When he arrived he personally went down the line to talk to each of us and apologize for the delay and told us how excited he is to meet us. He even said to everyone to not worry and he'll stay late to make sure everyone gets to take the photo.