The computer can't backup and be asleep. So, you have to schedule it.
Schedule what? The backup job
is scheduled.
How important is sleep? Mine never sleeps - but I physically turn the monitor off when I am not present.
I dunno. With an SSD system drive it takes only about a second for the computer to wake up, so it seems like something of a waste to
not allow it to sleep.
Also, is it necessary to back up daily? I do it weekly and it serves me just fine.
I'd just as soon not have the potential of losing six days of work, even if it were only email messages and a few spreadsheet edits. Running a scheduled backup job isn't exactly like busting rocks with a sledgehammer. Running it daily is no more work for me than running it once a month. The only real resource used are a little power and some disk space.
I have it run a virus scan SUnday morning while I am at church. That works. AV definitions come every day at 0400.
Schedule your computer activities around yours.
If the computer is going to sleep after 20 or 30 minutes of inactivity, I'd have to either launch it manually or else schedule it to run when I know I'd be at the computer. I don't have nearly that set of a schedule, plus I'd prefer that it run while I'm not using the PC.