I think the author was indicating that while you can use that syntax to declare and initialize variables, you can&#x27;t use it later to assign new values to them. I don&#x27;t think they had any problems with the concept of `let`.<p>And it does strike me as a little weird as well to only be able to take advantage of the pattern match destructuring on initialization, but I&#x27;m sure there&#x27;s a good technical reason.