Dad’s short answer: Vacuum first, always. Carpet cleaners aren't hair-removal machines — wet hair wraps around brushes and clogs hose tools, and any hair left in the carpet turns into a mat once it's wet. Five minutes with a vacuum saves a lot of aggravation.

Why hair is a problem when wet

Dry hair vacuums up easily. Wet hair clumps, sticks to everything, and wraps around a spinning brush far more stubbornly than dry hair does. It also blocks the narrow throat of a hand tool, which kills your suction without being obvious.

Hair left in the pile also traps the cleaning solution against the carpet and slows drying, and it mats into visible clumps that look worse than the stain you were treating.

So the rule is simple and it's the single most useful piece of advice in this whole category: vacuum thoroughly before you deep clean. Every time.

What the better machines do about it

Some models have hair-management designs on the brush roll — combs or anti-wrap geometry similar to what good vacuums use. Worth having if you've got a shedder or long hair in the house, and it's a feature worth looking for by name.

On hand tools, look for a clear window so you can see a clog forming, and tools that come apart for rinsing.

Whatever you own, check the brush and the tool after each job. Hair left wrapped on a brush and put away wet is how a machine starts to smell, and it's the most common reason people say their carpet cleaner went bad.

This is also worth saying plainly: if your real problem is hair rather than stains, that's a vacuum purchase, not a carpet cleaner purchase.

Dad’s Take: Vacuum first. Every time. Wet hair is the difference between a clean job and an hour of picking clumps out of a brush.