Only if you’re actually going to mop — but if you are, it’s the difference between a feature you use and one you abandon by month two. A cold rinse leaves the pad dirty enough that you’re smearing yesterday around today’s floor.

The two problems hot wash solves

The first is dirt transfer. A mop pad rinsed in cold water without agitation holds onto a surprising amount of what it just picked up. The next run puts a good portion of that back down on your floor. Hot water with real scrubbing action in the dock gets the pad genuinely clean, which is the whole point of self-washing.

The second is smell. A damp pad sitting in a dock in a warm house starts to go sour within a few days. This is the single most common complaint I hear from people who bought a mid-tier combo with a rinse-only dock. A hot air dry cycle after washing solves it completely.

When to skip it

If you’re buying a robot to vacuum only, skip this entirely and put the money into brush design and navigation instead. You’ll get more out of it.

If you have almost no hard floor — one small entryway, say — the mop is a minor feature for you and a basic pad you rinse yourself is fine. The hot wash dock earns its keep in homes with a lot of hard floor where the mop runs several times a week.

Dad’s Take

Cold-rinse mop docks are how good robots end up with the mop feature switched off six weeks after purchase.