Dad’s short answer: It picks up dry debris in the same pass as the wet cleaning — that's the whole reason the category exists. Cereal, crumbs, dry dog food, dust. You do not need to sweep first, which is most of the time saving.

What one pass actually handles

Crumbs, cereal, dry pet food, dust, and small bits of leaf and grit tracked in from outside all come up in the same pass as the mopping. The roller catches them and the suction carries them into the dirty tank along with the water. That's genuinely how it works in my testing, not just on the box.

It's worth understanding that these come up wet. They end up in the dirty water tank as a slurry, which is why that tank needs rinsing after every run rather than just emptying — food debris sitting in a warm tank is a smell problem within a day or two.

What to pick up first anyway

Big solids. A whole dropped cracker, a chunk of dog food the size of a marble, anything stringy. Those are what clog the suction tube, and the long thin brush in the box exists precisely because that happens.

Anything sharp. Broken glass should be picked up by hand, always.

And construction grit. Not because the machine can't lift it, but because dragging grit under a roller is a scratch risk on a soft floor finish.

Everything else, just run over it. That's the machine's job.

Dad’s Take: No sweeping first. That's half the reason to own one, and people keep sweeping out of habit.