I think the reason for that is similar to why animes tend to be alot shorter compared to the manga. While this webtoon does have a novel origin, not everyone would have read it so it would be very difficult to transfer all the contents from the novel to the webtoon as it could be very overwhelming. For this reason, whenever there is an adaptation of a novel or manga etc, it is often you will see only the mainstream ideas being produced and it progresses alot faster inorder to hold the readers/viewers attention.
(Just my opinion)
That’s true, which is such a bummer
For some reason, I find that this webcomic is too rushed? The novel is a slow burn and you get much more insight into Cale’s mind and that gives you more understanding of the plot. On the bother hand, the webcomic just grazes by and leaves out many small, but important details, making some scenes seem nonsensical due to that.