If you find someone who really knows how to clean stuff, you’ll find that you don’t always have to dry clean things. The people who handle theater costumes know a ton about this, but you’re down to hand-washing in cold water with a little dish soap which takes a long time so most people just send them in.
No one here has yet mentioned that after the suit comes out of the washing machine, an expert with a steam gun/steam press re-forms any area of the suit that was bunched/wrinkled so it looks as good as the day you bought it.
The average person doesn’t have the technical knowledge to get it done at home.
Suits are relatively delicate and mechanical cleaning is hard on the fabric and can cause Pilling, damage to seams and linings, weaken buttons and fasteners etc.
Plenty of suits these days ARE machine washable, but they tend to be at least partially made of hardier synthetic materials. More expensive natural materials like linen, silk and wool are not as hardy.
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