Back in time, robot vacuums seemed like a futuristic luxury not for everyone. But today, everything has changed and these tech-savvy "flying saucers" make up 20% of the global vacuum market. The Roomba remains the most popular choice, making up 70% of the total robot vacuum market, with over 14 million units sold to date. Remember that this cleaning product comes at a minimum of $300, so their popularity is nevertheless surprising.

The iRobot CEO and co-founder Colin Angle told TechCrunch in an interview that the high sales of Roomba cleaners prove it’s “a steady business for a consumer product that starts at a price point that tends to be a bit higher than your average human-powered home cleaning hardware.” Meanwhile, Angle envisions home robots gaining more importance as homes get smarter.

But some critics claim that robot vacuums will never replace traditional cleaning tools because… well, they don’t do their job that well. According to NY Times, even the best robot vacuums barely touch the fine dust that settles into rugs.

“After six months of regular cleaning with the top-of-the-line Roomba, all of this debris still managed to pile up in a single 6-by-9-foot area rug.” The mess was cleaned in only 15 minutes by a human-powered vacuum.

Another con in the robovac department is that our modern homes filled with obstacles are not compatible with robots that easily get stuck in household clutter. Think of all the piles of laundry, small little items scattered around the house, charging cables, and all the other traps. These are a no-go for a robot vacuum and unless you keep your home clutter-free, it will be a hassle.

And lastly, in all fairness, not all robot vacuums look like they really know what they’re doing. Do an experiment: sit down, relax, and watch your bud moving around. You’ll see it bumping into obstacles, cleaning the same area for half an hour, and basically looking dumb and without a vision. The best way to avoid this is to stop watching and let it be.