nested keywords

I’ve taken the trouble of nesting keywords, such as putting Mustang under Ford and Ford under Automobile.

After taking the time to do this, I can’t see the benefit of this exercise. My question is, is there any benefit to taking the time to do this?

Please advise.

Thanks in advance.
Larry

Example:
Assume you only tag car files by model, like Mustang. How would you search for all Fords? Using a flat tag model, you would have to add Mustang, Ford and Automobile manually to a file. With nested tags as you describe, you only need to tag an item Ford. The other two tags come in automatically.

But there are other ways to accomplish the same thing but using a flat tag model.