Totally disagree here.
My clothes does not affect my thinking or any of my mental capabilities. I believe this is only true if you believe it — basically, your state of mind.
And if you do believe this, you’re making clothing your cruxes. Oh, I can’t perform because I’m not wearing my lucky cap or lucky t-shirt. This is no different from superstitions or rituals ppl feel a need to do so luck is on their sides.
And the old saying, clothes make the man, that is really referring to how ppl portray you. It is true that you have no control over how ppl perceive you and if you don’t “dress for the occasion”, you might be misunderstood.
For instance, going to a wedding with a t-shirt and jeans. This will be viewed as disrespect for the wedding couple and families. Going to an expensive car dealer in t-shirt and jeans — well, this can be easily misunderstood by the salesperson that you cannot the afford the cars here (a huge mistake, IMO).
Personally for me, I don’t really care what ppl think. I did buy my expensive sports cars in a hoodie and I have to say I was not treated well by some dealers during the process which is no loss here because I basically bought them from dealers that didn’t care. However, even for these dealers, they do look surprised when I say I take it. I also wear Gap and sneakers to work at a financial firm and I would only work at companies that don’t have a strict dress policy because as I was saying, it’s the work that matters and my work in no way is affected by what I wear — the caveat to this is it would probably be affected if I wore a suit and tie because the tight collar restricts my circulation and most fancy suits happen to be uncomfortable.