Observed absurdity

Ok, here's a pet peeve I've been petting for a while.

Scene:

A meeting at work where the conference line is open.

Seen:

Admist heavy discussion whether it would rain heavily this weekend or would it be sunny.. Oops that was going on in my mind. I waver every time we have a meeting and I can't get enough from 8 people repeating the same thing 8 times. Well, I mean I waver every time we have a meeting.

Well the actual discussion was about "should we update something in one place or update something in both places". That's not important here. When someone says something seemingly important, the caller on the conference call goes "I can't hear you, can you speak up please?" and at least one person sitting by the phone relentlessly INCREASES THE PHONE VOLUME
ON OUR END".

I just don't get it. What does the person increasing the volume think in his head??

"I can't hear you"
(Increasing the volume) "Well, we can hear you, and now we'll hear you better now."

"I can't hear you"
(Increasing the volume) "Oh here we go, pushing up the phone volume increases the vocal chord pitch of every one in this room, how cool"

"I can't hear you"
(Increasing the volume) "Too bad for you, now at least you can hear yourself louder"

"I can't hear you"
(Increasing the volume) "Oh let me do a magic"

I am not kidding, I have observed this absurdity at least 11 times by 11 different people. Common sense like they say, is so uncommon!