system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are cab-over trucks virtually non-existent in the US, but used almost exclusively in other countries?
gpt
The USA is a spacious country. Design trade-offs that reduce the truck's length are not as valuable when you have lots of room. And the USA is a large enough market to have its own truck designs.

Note that other very spacious countries (Australia, Canada) also have lots of non-cab-over trucks.