> I've never understood why people do this on block level elements like paragraphs and headers where default behavior should definitely be margins. IMO it’s mo

> I've never understood why people do this on block level elements like paragraphs and headers where default behavior should definitely be margins. IMO it’s more correct semantically. An <h1> means the top level of page heading, it doesn’t mean “1em of margin at the top and bottom”. A CSS reset that also resets all margins etc lets you derive your own formatting rules from semantic HTML. In most cases this is all a nitpick but I do get the rationale.