It does. You betcha.
It doesn’t matter if you dress sharply, look sloppy, smell bad, forget your tie when everybody else has one, pick your nose in meetings, and so on – it WILL make an impact. Someone might think, hmmm…this guy/ girl is…weird, smelly, good-looking, seems to be in control, elegant, ugly, skinny, fat, interesting or disgusting. People will think something and you can affect what they think of you. If you think you can’t, you’re in trouble.
Appearance matters. If you’re (for example) really fat, people might think you’re lazy. You might not be, but there is quite a risk that people would think you don’t take care of yourself, you can’t say no, you fall for temptations, etc.
If you’re going to an interview in a dirty suit, wearing some cheap shoes or sweating profusely, this will very likely lessen your chances of getting the job!
Appearance is a part of who you are, it’s an important part of your personal brand. The clothes, the hair, the care you put into yourself reflects the kind of person you are and can be very beneficial or detrimental if you don’t pay attention to it.
Because believe me when I say that others will.
Image: Ryan Gosling being very “vain” in Crazy Stupid Love. His character understands the importance of appearance.