What happens if an asynchronous function finishes without an explicit return statement?

If an asynchronous function in Node.js completes without an explicit return statement, it automatically returns a Promise that resolves with the value undefined.

For example:

async function example() {
  // no return
}

example().then(result => {
  console.log(result); // undefined
});

This is important to consider if the calling code expects a specific value from the asynchronous function — the absence of return will result in the result being undefined.