This is fine if you have been paying attention to everything up until that point.

This is not so great if you came in a bit late and want an overview of everything about the story.

In other words, wiki forces users to collaborate on the same extended piece of content. This has all sorts of great effects, if enough people are participating. But it makes it harder to make short fungible pieces of content, rearrange them by vote, and do contests to discover the best version of each type.