Because you probably don't shave daily and your facial hair doesn't look good in a state of partially-grown in. You need to either rock the clean shaven look, or you need to commit to a mid-sized beard and keep it trimmed and looking good.
While you are at it, your hair is a bit long. Go for a shorter look, you can keep the front a bit longer to stylize but the sides should be above the ear, back is rounded, not squared.
Your wardrobe could use some work, pullover sweaters look shitty on anyone that's not a busty chick, you need to invest in a nice leather jacket.
Your shoes could use some work, I would recommend a nice pair of slip-on Vans, they are about $60 but one pair will last you upwards of a year, and goes well with any look.
Now for your pants, you want to go a bit slim fitting, but not nut-huggers. A decent looking belt would tie together the look, and a good belt is only like 10 bucks.
Also hit the gym, fatty.