My take on this is as above. He was totaling up his hours for the month or year and needed the time. This may explain why it was handwritten as well. That takes awhile.
A text would take next to no time as there would be no lengthy preaching.
A phone call? Well that easy, you may not answer, and if you did you may not listen to his lengthy speil. No time to speak of for his reportβ. Sidenote - It was a waste of paper and is added to a landfill. π