Because JS will always be compromised by being JS shoe horned into a role it wasn't designed for and not byte code optimised for the purpose at hand. Shoe horn

Because JS will always be compromised by being JS shoe horned into a role it wasn't designed for and not byte code optimised for the purpose at hand. Shoe horning technologies into roles they weren't intended for could describe the entire scope of why the Web sucks (e.g.: HTML mixing presentation with semantics).