Why is one battery marked #1 on the Voyagers?

[BobVA]

(12-06-2018 03:25 AM)jonese Wrote:  ...I wonder if HP thought there could be possible damage to the conductor or worse the board if the battery were slid in sideways....

Or perhaps, if the user had a static charge, that it was safer to discharge it (via the battery's metallic shell) to the ground side of the board rather than to the V-bat terminal, where it might cause damage or lock up?