It also forces the resource to load if it does exist, which makes load order issues less problematic. A lot of people reporting issues like “export doesn’t exist” because they start an (optional) dependency after the dependent resource.
That early failing is pretty much the desired effect, at least for me, though – many other errors may result simply because a dependency doesn’t exist or hasn’t started yet, but I would need to rely on people modifying fxmanifest to add a dependency when enabling e.g. ox_target integration instead of distance checks.