hello, I want to say this is a great sketch! Somethings I could say that need to be improved on is the way the guy walks - it looks like he is being bumped forward that his head goes down a bit too much and a little too hunched from a straight back. Something I learnt in animation drawing, a technique I would suggest to you if you havent already done this is make a light box from a normal plastic box (such as a hobby box type of box) cut in half and slanted down, like a graphics table but a lot smaller. Then insert a light in it - perhaps rip a light fitting from a lamp, keeping the power plug attached to the light, and make a hole in the box to put the light inside. Then make the top with a perspex that you can semi see through, white is best.
Then get an A4 sized paper, draw up a square, that will be the field area to work in, then keep that field square as the underlayer to keep track of position when drawing a series of movements. Do the first drawing of the character on a new piece of paper over the field square drawn one, then leave that on the table, and start the 2nd one on a separate piece of paper on top of the 1st drawn one. Then remove the 1st one when you have done the 2nd one, and do the 3rd one on a new piece of paper, over the 2nd one. That way you can see almost clearly the movement positions.
Also I'd suggest doing the hair a little less movement and more uniform movement. The hair seems to change too much in each movement making it look like a new person in each position. Hope all this helps. You did a good sketch and I can see great potential for this to be in a game by you.
Then get an A4 sized paper, draw up a square, that will be the field area to work in, then keep that field square as the underlayer to keep track of position when drawing a series of movements. Do the first drawing of the character on a new piece of paper over the field square drawn one, then leave that on the table, and start the 2nd one on a separate piece of paper on top of the 1st drawn one. Then remove the 1st one when you have done the 2nd one, and do the 3rd one on a new piece of paper, over the 2nd one. That way you can see almost clearly the movement positions.
Also I'd suggest doing the hair a little less movement and more uniform movement. The hair seems to change too much in each movement making it look like a new person in each position. Hope all this helps. You did a good sketch and I can see great potential for this to be in a game by you.
Got that in my application letter. Wish me luck! Really hope I get one of the jobs. Design printing company.
. Now the question is why people are like this in general, many are. Maybe it is because they dont know us? As Oliwerko said, it could be because they feel that way too? Afraid to be silly. Maybe they are afraid to be too friendly to people they dont know? I tell you though, it makes me feel warm and fuzzy inside when someone I dont know is friendly or smiles at me at the shops or in the streets. I find cold people a bit hard to deal with thats why this is a topic I ponder on a bit 
. Thank you guys for solving this aspect for me.