I have following code snippets:

const x = () => {
  return Promise.resolve("X1");
};

x().then((message) => {
  console.log(message);
});

vs

const y = new Promise((resolve, reject) => {
  resolve("Y1");
});
y.then((message) => {
  console.log(message);
});

I understand the resolve in the second code snippet is like callback. Not sure about the first one, under what cases we need call Promise.resolve?