The Neato vacuum does a back & forth pattern. But after living with a Roomba for a while, I've grown to appreciate their mostly-random pattern - it (eventually)

The Neato vacuum does a back & forth pattern. But after living with a Roomba for a while, I've grown to appreciate their mostly-random pattern - it (eventually) makes sure that the nap of the carpet gets brushed in different directions, so your carpet doesn't look like the greens at the local golf course, with stripes in it.