Everyone wants their brand to stand out.
Your logo should stand out on the background color. Most people’s first instinct is to choose a company shirt that matches their company’s colors. That’s a great idea, but only if the logo works with the color of the shirt.
If the logo is red and the customer wants a red work shirt, to match their brand, the logo will not stand out well.
A red work shirt with a white version of the customer’s logo.
A tan work shirt with the customer’s red logo.