Comment by belltaco

The issue is with OCR. Imagine something that was printed(for being physically signed or filed into a cabinet, for example) and rescanned into an image or PDF. Both printing and scanning is lossy with lots of noise and artifacts. The article is saying that serif fonts are harder to OCR.

For example, something like this https://h30434.www3.hp.com/t5/image/serverpage/image-id/6945...