Ring has so many bad reviews because: Poor Hardware / Poor Software / Poor Customer Support / Poor Infosec.
I will address these in the order mentioned.
The hardware is poorly made:
(1) For example, the constant bell ring would suggest the button sticks. Yet they have not changed the button on new models from the older one I have. I had to stick my button back on with glue when it fell off.
(2) The GainSpan modem has to contact their servers and then ring on your phone ,tablet or PC, so, by the time you get the alert the visitor or thief has gone. They can't do anything about this because it is a limitation of how the device is made & they want your information more than they want you to be happy as a customer.
(3) And worst and I mean flat out worst, even when presented with real problems they just flat out won't accept that, for the stated purpose at least, their product doesn't work. It IS NOT a bloody doorbell if it doesn't ring quickly enough when someone is at the door. IT'S NOT A DOORBELL!
(4) Information security of users: Oh boy where to start. I approached their customer service people because I felt my doorbell had been hacked. They told me that was impossible because they had 'bank like' encryption. Having worked in IT I had no idea what that was and I am pretty sure they didn't either. They gave the kind of glib responses that don't suggest any degree of IT knowledge. Point of fact, banks get hacked all the time!
Back to me, my doorbell volume kept being turned down when I hadn't touched it, my videos were displayed out of order and it just felt like someone else was probably watching my front door footage for these reasons.
So I ended up doing a SAR (Subject Access Request) and found another user and owner registered on my doorbell. His email address was for his private blog and I won't give it here because I am fairly sure that he doesn't work for Ring.
Here comes the crappy bit for customer service, despite this guy being registered on my account their Ring Rep tried to blag that the guy was a warehouse tester and not registered on my account despite him coming up on my Subject Access Request. By the by, the Ring people know, I mean know, that owners are not kicked off when the close their accounts according to the online article below.
'A Ring doorbell vulnerability lets people snoop even after a password change' Lulu Chang https://www.digitaltrends.com/home/ring-video-doorbell-security-exploit/
So their customer services people are lying about issues and their software people are not fixing problems.
That, along with sickly sweet, glittering generality replacing honest customer engagement, is why in my opinion they are getting so many complaints.