Comment 1 for bug 1577950

This is a requirement for devices that have neither discrete power switches nor removable batteries. Without this feature, if the phone locks up, it cannot be turned off and is completely non-functional until the battery dies, which also damages the battery.

The volume issue is non-orthogonal, but do note that changing the volume outside of phone calls is important. As described, you would have to call a friend and keep them on the online while you adjusted your ringtone volume. You'd also have to pause music and call someone and keep them on the line if you wanted to turn up the music volume a little. Or call someone and keep them on the line if you wanted to turn off alarms or raise their volume.

Better to file a different bug to deal with volume, and keep this one for the power issue.