Growing up we always had a central vacuum. If you're not familiar, it's exactly that, a permanently installed "central" vacuum, with pipes running to various outlets where you plug in a hose and normal vacuum attachments. The advantage is they are hilariously powerful, but also very loud.
Needless to say, the house was clean. I quickly became accustomed to carpet always being fluffed and soft, without a spec of dust to be found. Not only do central vacuums have strong suction, but they have powerful "beaters" that agitate the carpet.
This is my robot vacuum. It's a cheap model that was listed for $15 because it didn't work.
I disassembled it, cleaned it, replaced the battery, and fixed the front bumper by tightening some screws, and suddenly a robot was cleaning my house.
The main design challenge with a robot vacuum isn't the robot parts, it's the vacuum. Fitting a powerful vacuum into a small space that runs on the low voltage of a battery is hard.
Robot vacuums don't agitate or create as much suction as a quality vacuum or especially a central vacuum.
So why do I highly recommend them?
They make up for it with frequency and size.
You need all of that suction because it's been a week, or a month, or worse. Robot vacuums can run every night, or whenever you choose. They can easily keep up with normal dirt and debris. Mine also performs exceptionally well on hard floors.
"Normal" is important, if there's more than they can handle, they might not catch up unless instructed to run more often or as often as possible.
Another advantage? Height. Mine goes right under the couch, where I can't even reach. Same with my bed. There's no way I can clean that well without moving the whole couch.
Don't throw out your normal vacuum, but robot vacuums are a fantastic investment, and even the inexpensive ones pay for themselves.
My only purchasing advice is look for quality software and apps to go with it, you want it to be easy to control and operate from the app.