my galaxy S stopped taking calls and/or text messages the other day. I went into the AT&T store to complain and they guy asked me if I had restarted the phone. I said 'of course!' but it did not help.
So he left the cell phone turned ON, then opened it up & took the battery out. After replacing the battery and restarting it, the phone worked fine. He told me that's how you give these things a hard reboot...just the way it's done.
In my years with electronics & computer repair, we are taught to NEVER unplug or plug in a device while it's turned on. Even batteries.....
Seems that it worked fine though, and I'm just sharing.
You are right.
Doing that does harm to the phone as you may suspect. What he should have told you is do backup and do a Soft Reset.
Taking out the battery of a Running phone like that at the wrong time can accelerate wear and tear or worse break the SSD.
Imagine you get a call, and the phone is getting ready to ring, but you pull out the battery. The ringtone was being called from the Drive to RAM, and where the I/O was being processed you pulled the battery, that is detrimental to both the RAM and Drive.
And the Drive in these things are already given a set number of Read/Write Cycles, accelerated wear will just reduce the number of Cycles you have left.
The Root cause of the problem is buggy software, usually caused from residue settings from a recent Update