incidentally, the fact that Await is not called on nextValue means that it's actually possible to cause the loop variable in a for await to hold a Promise if you construct the async iterator manually, though you should not do this:

let x = { [Symbol.asyncIterator](){ let first = true; return { next(){ if (first) { first = false; return { value: Promise.resolve(0), done: false }; } else return { done: true }; } } } };
for await (let a of x) console.log(a); // prints a Promise holding 0