Gold Roger
First Post
I think that is because there are more than one entrance so you can face multiple different encounter difficulties.
Orcs are tough (but few), kobolds are easy (but multiple), and hobgoblins are in between.
That's definitely a part of it. But I've seen very different reports where groups took the same entrance.
One big part of it to me, is that the module leaves a lot of stuff up to the DM. For some that might be a fault, but after digging in, I enjoy seeing how much I can adjust it to my own DMing style without any real work.