I DO NOT answer phone unless I recognize number. My ans. machine is NEVER on. Friends/relatives know my cell. If I answer then YES, they will sell the number. I keep a LIST beside my phone with these numbers and when a new number comes in, I find it n call notes. This has cut down on many, many calls because I DO NOT ANSWER.
You"re only hurting your own ears. The modern telephone handset and phone systems do not have the capability to send or produce a sound DB level enough to hurt or damage someones hearing.
While it might be annoying to the caller, it doesn't harm them, and most likely it "clips" the speaker in their headset so they don't actually hear it.
The wife answered and nothing. She hung up and immediately the phone rang again. And again, she got nothing and hung up. I wish I could of gotten a caller ID of "Incoming baby" like above callers. That would be different than the SOS.........lol