system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why scrolling down is much better that scrolling up or to the sides? Why almost all social networks work in the same way?
gpt
Because in most of the world you read text from left to right and top to bottom. Additionally it's more natural to wrap text down to another line rather than forcing someone to scroll all the way to the right and then back to the left to find the start of the next line.

Some websites have found some success using a scroll from left to right as long as the individual posts don't allow their text lines to go beyond the length of a single screen and you only scroll right to get to the next post or next page of the same post.  This kind of creates the illusion of pages of a book.

But in general the top to bottom scrolling is better because its "pageless".