Exactly. If you write a crummy contract but believe it is sound, then set out to convince other people of it soundness, and they sign up and pour their money in, and then the contract leaks, who's responsible? ... well, next minute: lawyers.

We'll first have to invent, and deploy at scale, the immutable person before we can have the perfect contract 100% of the time.

So long as people change, minds are fallible, misunderstandings and disagreements continue to occur, interpretation and intent are going to be fuzzy.