What were they thinking?
Keeping the 'GND' point centred between CH1 and CH2, as they're the two channels that can be set to Series / Parallel operation.
Then, to make the connections mirrored, shift one channel to the left.
It seems fine, as the buttons are (thankfully) in the same physical orientation as the outputs.
Maybe better to shift the 'GND' to the far left or right, but I guess it's a convention to centre it like this.