But WHY stick onions with cloves!? (lighthearted)

My mother always admired a famous chef called Philip Harben(?) - not sure of exact name anymore. She said she liked him because he didn't just tell you WHAT to do but also WHY? When motives are explained, they are so much easier to remember.

My question would have been "Why, when we are making a broth or certain other meat dishes, do they tell us to stick cloves into an onion? Is it just for tidyness - not to have cloves floating around our dish - or is there some miraculous alchemy that occurs when we stick our cloves into the onion?

I've always obediently followed instructions but have always wondered if it is important to do so or not?

Is this a stupid question?