Not really, because it continually adjusts its schedule for you depending on your manual inputs, is powered by the HVAC wires themselves (and charges a small backup battery that you never have to worry about), and if you really wanted to you could log into her account and fix the thermostat remotely if somehow she managed to really break things. If all you do is turn the ring right or left for colder and hotter, it'll do its thing just fine.

You could hop into the menus and.. forget the wifi password or something I guess?

One thing nest handles really well is "I'm feeling a little too cold/hot tonight and I'm going to adjust the temp". You walk up and twist the ring and you're done. You don't have to disable scheduled mode or enable override mode or anything like that. Twist and done. I have a feeling that's how grandma messed up her thermostat, she was feeling cold so she turned it up to 80 (lol) and then the thermostat said, ok I guess this is my life now. 80 degrees forever.

I hate that this sounds like I'm arguing, because I'm not. I just find this discussion interesting.

If the device learns over time from grandma turning the dial up and down, does that not create strange data for the device to figure out? Take your example, grandma is cold so she turns the temp up; does this count as a manual input? Does that not eventually create a problem? Much like the original thermostat but takes longer?

Although, the account thing is interesting. Can you set the schedule and then disable the manual interface to let grandma change all she wants with no changes?

Heh, no offense taken.

I don't know the internals of how nest deals with wild swings in manual inputs, but I haven't seen a problem. Although even if it results in a "nights are 80 degrees" situation, the rest of the day is unaffected so at worst it's still better than the other thermostat.

Yes, you can set a schedule and disable the physical interface.