Why git tag a blob or a tree (or a tag)?

Question

I understand how it is possible to tag a blob, or a tree, or even another annotated tag, using a git tag. I understand the architecture and conceptual design that

Answer 1

Tagging trees or blobs may be appropriate temporarily in long-running utility programs that manipulate objects directly. Tagging would ensure that git gc can be safely run in parallel. The utility program would then remove the tags when it's done, when it's created a commit.