The following causes a runtime error:

function factory(callback) {
  callback();
  return () => console.log(
    "crime performed");
}

const func = factory(() => {
  func();  
});
// TypeError: func is not a function

But the following works:

function factory(callback) {
  callback();
  return () => console.log(
    "crime performed");
}

const func = factory(() => {
  setTimeout(() => func(), 0);
});
// "crime performed"