Those smart telecom engineers usually did things logically for a reason. For example, crossbar systems were always built from the outside in so that you didn't have to pull the crossbars all the way out to add equipment. The CO's usually got populated from top down, but the carriers from bottom to top. It made it a lot easier to set your new equipment on top of the existing instead of trying to horse the cabinet underneath existing shelves.

Panasonic TD systems number from bottom to top. Your CO jacks for 1&2 started on the bottom and the AMPS for 101-108 are on the bottom. Even the Mitel SX-200's built from bottom to top, both in the analog 200, 200D, and 200 ML/EL.

The thing that made glare so important back in the day was the CO ring generator (at least ours) was 2 seconds on and 6 seconds off. If you made your phone call in on the 3rd real time second, you had 5 seconds before the ring generator came back around. Anything could, and did, happen in those 5 seconds. Not everyone or every system had ground start trunks (oh those were extra).

Of course step switches numbered from bottom to top, but that was a function of counting :-)

Carl