Complicated story, I can tell it quick. I had been scheduled two months before a Sunday talk. I did not know anyone at the cong. Nobody called to make sure I was coming, but I went to the Kingdom Hall. I introduced myself to the PO. He said that the brother who had scheduled me was no longer the talk-coordinator, but the new PO (the guy in front of me) was doing it. Then he said he had gotten another brother on the schedule for today.
"Okay, then you don't need me, fine, no hard feelings."
"Well, that brother called 20 minutes ago and cancelled."
"Then you do need me, okay."
"Well, I called [Brother Popular Speaker] and he's on his way."
I knew that brother quite well, when he showed up, he asked if I could give the talk since I was obviously prepared and he wasn't. The PO said "I don't know this guy." The two of them actually had an arguement about it two minutes before the meeting starts. Brother Popular Speaker insisted that I was a good speaker, but I said (to both of them) that if this PO was that insistent, there was no way I would step on that platform.
I went back and gave a talk there, about a year later, and the PO approached afterward, saying "You did okay, we should have let you speak that time."