Look at it like this: For each component you add to the chain, it resolves the next path as if it was standing at the path so far and resolved the new component from there. (a sequence of `cd`s, if one could `cd` to a file)

It makes no sense for any component to start with a slash, even though I see how that might happen (e.g. git encourages you to make relative-absolute ignore paths, or it will apply the filter in every subdirectory).

Still, it's a good quirk to know about when validating user input.