- Part out of habit (since way before 'Do not disturb' mode), I want no disturbances when I sleep.
- Because it saves battery/energy
- No connected device in the bedroom (OK, I got a Kindle)
- I (honestly) don't see any sense in having my phone run for ~7 hours while I'm asleep
On new devices it hardly saves any battery because iOS (or maybe just the latest iPhones) have become wickedly good about preserving battery when idle.
Sure, that makes sense. I hope my peers don’t call me, but emergency services if something bad happens. And my immediate family is at home with me. And I have an alarm clock on the bedside table ;)