There’s a classical studies word for that pattern: boustrophedon, with the same agricultural origin and motivation, only it refers to oxen ploughing a field, not a lawnmower mowing.

Online Boustrophedon:

https://codepen.io/pouretrebelle/pen/pvOxvv

(you may need to reload if the text isn't justified properly)

Nice word, I was always looking go see if I could use it in any real world sentance.

But I thought it came from some form of writing that alternates left to right and vice versa.

The writing form is named after the oxplow motion.

This is a good argument against horizontal scrolling. They make the point that it's good be able to select just the columns you want. The broader design question is what columns (information) will best support the user's judgment to be made - as expressed through the comparison at hand.

Why wouldn't user just use the same pattern turned 90 degrees for horizontal scrolling?

I'm super again horizontal scrolling, but I'm not convinced that this is an argument against it.

> Why wouldn't user just use the same pattern turned 90 degrees for horizontal scrolling?

Could be it doesn't work as well; while obviously eyes can move in n all directions, it's possible long left-right sweeps with small up-down adjustments are more natural/comfortable than swapping the axes.

Certainly horizontal scanning seems to be more a common activity generally, so it would make sense for it to be favored.

Anyone else mow their lawn spiraling inward?

Just Once. That was enough.