Anticipated issues with 24/7 operation

[esk114]

Have had a CM600 and AC3200/R8000 running for quite a few years now.  Been amazing for day-use, and, have powered-off at night.  

Our current security system has been doing very well, but, want to expand with wifi add-ons.  This means leaving the modem/router running 24/7.

I've searched in the Community forums and the Net, but, have found only issues with power outages and sporadic power-off/on items.

In anticipation of leaving the gear powered-on 24/7, what are some issues I can anticipate?

What have been experiences with similar products from the Community?

Should power-downs be performed, and if so, how often?

I'm one of the few, from talking with others having different gear, who do power-downs.  I'm looking to be prepared for anything that "might" happen when I don't turn-off the switch.

[FURRYe38]

Modems are ment to be online 24.7. Unless there are signal line problems or your troubleshooting ISP issues, modems are left ON always. There are no reason why they need to be powered off. Unless your going to be away from home for a long period of time. 

[antinode]

> Modems are ment to be online 24.7. [...]

   A simple modem should be so simple that such problems (even using
Netgear firmware) should be very rare.

   Routers are also intended for continuous operation, but Netgear
manages to provide firmware which can fail in various ways after
up-times of hours, weeks, or months.

   I have no experience with an R8000, but I have had repeated lock-ups
on my D7000[v1]:

      https://community.netgear.com/t5/x/x/m-p/1782476

> [...] I'm looking to be prepared for anything that "might" happen when
> I don't turn-off the switch.

   In my experience, you can expect problems eventually.  I've never
seen any reason to expect a daily restart to be beneficial, except that
it could prevent the longer-term problems from occurring.

   The choice seems to be prophylactic restarts at some interval
(determined by experiment?) or responding when a failure occurs.  Or, of
course, using equipment with more reliable firmware.