Somehow, “garnish” means both “the little decorative things chefs sometimes put on the plate with the rest of your food” and “to take money out of your paycheck without your permission to pay off your debts.”
We don’t know how this happened. The two ideas aren’t related at all. But it’s the second meaning we’re interested in, because it makes “garnish” one of those special words that doesn’t sound anything like what it actually means.
Sometimes we use words to distance ourselves from our actions.
If you and I were in charge of getting money from people who weren’t paying their debts, we might find it easier to get through the day if we never had to say words like “seize” or “steal” or “take by force.” It’s a lot easier to say, “We garnished your wages because you defaulted on your loan” than it is to say, “We’re taking your last little bit of money and giving it to somebody else.”