These are principles, not mathematical equations. It’s like drawing an human face. The general rule is that the eyes are spaced by another eye length viewed from the front. Or the intervals between the chin, the base of the nose, the eyebrows and the hairline are equal. It does not fit every face, and artists do break these rules. But a beginner breaks them for the wrong reasons.

So there’s a lot of heuristics in code’s quality. But some time, it’s just plain bad.