I think they mean that the navigation is weird when you’re clicking Previous on the site. Here’s the overall archive:

https://www.oglaf.com/archive/

They mostly do 1 pagers nowadays, but if you go here https://www.oglaf.com/signs/ and then click “Previous”, it will take you to the first page of https://www.oglaf.com/goat/, with no indication that there’s a second panel that you can get to by clicking “Next” from that page.