My son is very laid back. For the most part, it’s a good thing. He does not freeze up before tests or freak out when an assignment is due. He just goes about his business and gets it done.
The down side to this is that he really only has one expression. It’s neither happy nor sad, it is just kind of flat (except before 10 am, then he looks just plain dopey)
He has started going to job interviews and this has proven to be quite a liability. His face and body language don’t give off the air of an enthusiastic high school student who wants to learn the ropes. To a hiring manager, he probably looks more like a bouncer at a club.
I have been talking to him about putting out a little more energy when he is talking to people but I’m pretty sure it’s falling on deaf ears.
People in the workplace, whether they are peers or managers, need energetic feedback. You don’t have to bounce off the walls but you need to be able to nod and make eye contact with at least some brightness in your eyes. Otherwise they will keep repeating the same conversation over and over because they think you are just not getting it.
Try it now. Stare at your screen with a flat “whatever” look. Now, pretend someone has just come in to take a photo. Sit up a bit straighter. Clear your throat. Crack your face muscles into a smile and turn on the lights behind your eyes.
I’m not saying you need a 10 megawatt smile to tell your boss that you are going to lunch but if you want the team to go with your strategy, then you need to get a little projection happening behind those eyeballs.
Recruiter's Couch 
So true! Every 4-8 months we interview co-op students, and if they don’t sound moderately interested and excited, they don’t make the cut.