Dry-cleaning, laundering, hot water, hot air, hot industrial-size pressers--these things all degrade your clothes. T-shirts develop pills. Buttons crack. Denim wears thin. Your cleaners will never accurately press your necktie's edges. They will flatten your collar. The tips of your shirt collars will discolor. Facings will shrink. Behold the litany of woes. It's not the wearing that decays your clothes; it's the washing.
I am a dedicated value-maximizer when it comes to dress clothing. (Consider, for example, these damnable pleats on my profusion of Jos. A. Bank suits. I am a young style blogger, yet I have all these pleats!) Every shirt that shrinks, every suit that wears, drives home the inevitable conclusion:
Do not wash/handwash/dry-clean anything until it takes on an odor or a stain.
I'm experimenting with wearing my dress shirts several times before washing them. I've found that as long as I hang them up after removal and spot-iron them as necessary, I can wear them two or three times before they need washing them.