Apologies for this, I’ve clarified this in my edit. I’d realised immediately after I’d submitted that it’s for a different purpose. Hope the edit clears it up a bit more.
Brevity is clearly an important quality aspect for all writing. But it does not come for free. For many people, writing concise documents is rather time-consuming, and there are certainly cases where you'd rather want to have a document at all, even if it is painfully bloated, than nothing.
I agree, and one of the examples is your use case - undocumented enterprise software. To go back to the title, brevity makes the documentation good, but I’d rather have bloated in-date documentation than no documentation.