Why plot at all
A screen shows the drawing instantly and perfectly. The pen takes forty minutes and gets it slightly wrong. The wrongness is the reason.
Ink pools where the pen slows at a corner. Paper takes up moisture and the second half of a long run sits a fraction differently from the first. None of that is in the file, and all of it is in the drawing.
It also enforces restraint. On screen there is no cost to another ten thousand lines; on paper there is an hour and a pen that is drying out. Compositions got simpler once the plotter started charging me for complexity.
The machine is old and slightly out of square. I stopped correcting for it after realising that the error is consistent, which makes it a signature rather than a fault.