Yep, I wouldn't use it for anything critical, if the lights don't turn on/off no harm done
Correct. First time I noticed it, with wireless sockets, was when I came down one morning and air pump, that is normally is on from 10:45pm to 2am was still on. Should have taken this as a warning
of disasters to come.
The timed remote sender was located in cupboard next to the switched sockets, as in the picture below. It runs on 433MHz, so shouldn't be affected by WiFi/Bluetooth, though some users report IR video senders (which I have), baby monitors and car keyfobs interfere with them. To improve reliability I used multiple off times on my 3 dosing pumps, so that if the first turn off failed, it might work the second time.
Final nail(s) in coffin for them was some of the switches failed, would turn on for say 5 seconds then switch off. Failing mains 240V capacitor that was underrated. I changed them to bigger rated capacitor and worked again, but never trusted the sockets again. Some were replaced under warranty, but newer ones usd different (more reliable !!!) radio code and were incompatible with my remote so was sent a new remote, which didn't support as many timer slots as original remote. All a faff really and might improve reliability a bit but will never be 100%.
This is why I built my PLC controller
https://www.ukaps.org/forum/threads/how-to-use-a-plc-to-control-your-fish-tank.42993/
Here it is just now, been running for 19,819 hours ( 2 1/4 years) with 100% switching on 12 outputs, no issues. Well chuffed.
.