Homepod connected to mains power

Although there are no specific guidelines regarding this, there are some things to consider:

. 

If you’re using HomeKit with the HomePod being a Hub, it needs to be powered on. 

If you’re using Siri for personal requests or to receive or make phone calls, it needs to be powered on. Or If you’re using it for alarms and timers 

It’s best to have automatic software updates turned on, so it needs to be plugged in, in order to perform them 

After being unplugged for too long of a period, it may not work as expected once plugged back in. Although my HomePod has been through many power outages, it seems to suffer a few glitches once power is restored.Having said that, I do unplug it briefly for one second when I feel it’s not behaving. I try not to keep doing the factory resets to remedy problems

For me personally, I want it to be plugged in at all times should I need to make an emergency call or text. I’ve used it for this purpose to call 911. I am also using it all day long for personal requests, timers and alarms. 

Ultimately it’s up to you and others can chime in here with their opinions on the matter

Although it’s ok to unplug it, I don’t think it should be left unplugged for long periods.