It was simply a way of getting information to the most people in the shortest time. It was used for many things, not the least of which was/is prayer requests, information/news dissemination, and evacuation/civil orders.
This post was edited by Thriftymaid at October 25, 2020 1:12 AM MDT
Us GenXers used it too. Sometimes I get sick of my entire generation being ignored. I was born in the best year of all - even boomers and 'lennials enjoy a 69.
The question rather assumes the listener would be incapable of understanding a concise, lucid explanation of anything!
I must admit I've never heard of "'Phone Trees" until this question, despite using phones since the days of rotary-dial instruments in coin-box, pay-on-answer public telephone kiosks; and often having had to complete contact and next-of-kin forms.
I though the best and clearest explanation is the first form and its instructions. That "flow-chart" symbology muddies the waters!