They matter so much that it is the first thing we look at when we try to buy a product that we do not know. If it catches our attention, we go over the details and maybe read a little more. But if it doesn't catches our eyes, it will go unnoticed. No matter how good it is, It will lose the opportunity for us to know it. If the product that attracts us is bad, we will know when we try it; if the product is great but did not catch our attention, it risk that we will never even try it.
Of course we are not products. Yet many times we find ourselves forced to compete, to excel, and basically to sell. The products have no soul, they have no possibility of improving their appearance and worse, they do not have a personality that influences the way they look. That's the main difference.
The fact of life is that you don't have a second chance to cause a first impression. Your appearance communicates all kinds of information about you. Over time, people will get to know you for who you are but when you first meet them, everything they know is what they see.
I met a young woman who worked as a reporter for the legal section of a local newspaper. She had dealt with hundreds of court cases, and confessed to me one of the first lessons that she learned to get information:
"You don't have to be a lawyer, you just have to look like one."
She began, -she told me-, to dress like lawyers, and learned to ask for documents like lawyers do. And of course, the files were released to her immediately.
In particular, I have never been impressed by appearances and I do recommend that you never get impressed by them too. But what I learned is that almost everyone else does it. And it is not only a matter about what you wear, but also how you wear it. Your speech, your posture and attitude, all those are part of your Visual Impact and it supports a certain impression. And the results can be very powerful. People will remember who you are. And it will be a positive memory.