Good answers are concrete and confident. For shrinkage, you want a number: "Expect 3-5% shrinkage on first wash if you tumble dry low." For dye lots, a solid supplier will say something like "We match dye lots within 10% tolerance, and we'll note the lot number on the invoice." That's a real answer.

Also listen for what they don't say. If they never mention pre-shrinking, ask directly. If they don't offer care instructions on the label, that's a legal issue—the FTC requires it. A good supplier will point you to the care label and walk you through it.