First impressions are king! It's a fact, that people tend to not change their initial opinions of someone. If you think someone is cocky and stuck-up, that probably won't change; nor if their creepy, or perhaps a 'fun' person.
Recently one of my classmates and coworkers told me that when he first met me, he knew that he wouldn't like me. Just taking a look at my face, he thought we wouldn't get a long. Well, according to him, I am perhaps the only person that has managed to change this initial opinion of his. Pretty cool...I'm not sure why, perhaps maybe my authentic self shined through.
First impressions are still important, as I doubt this situation will replicate hardly ever again.