I&#x27;m not sure how implementation is &quot;completely irrelevant&quot;; if that were the case then the entire conversation is essentially irrelevant as we could potentially implement any compiled language as an interpreted language.<p>The piece I quoted indicates to me that the parent possibly does not understand this about JavaScript since they stated the compilation cost of JavaScript &quot;is zero&quot; that implies that JavaScript is not compiled.  If there is a compilation step then some cost is incurred no matter how low.<p>It was further supported that the parent may not understand JavaScript is typically compiled when they followed on with &quot;cost being completely amortized with everything happening directly at runtime&quot;.  That would indicate that all of the cost is incurred&#x2F;paid at runtime rather than in the compile step which is simply false.