It’s not about need exactly, it’s about a writing convention. Also, we do have these pauses in our speech/that’s where we would insert those pauses naturally, they’re just often very subtle.

A lot of language, no matter what you speak, has a lot of these subtleties that are so engrained as to be almost unnoticeable. I’m at a pretty high intermediate level French and, because of the closeness with English, I’m actually learning quite a lot about why English is the way it is, too.