sleep is not waiting in for loop in javascript code example

Example 1: javascript sleep

const sleep = (milliseconds) => {
  return new Promise(resolve => setTimeout(resolve, milliseconds))
}

/*Use like so*/

async function timeSensativeAction(){ //must be async func
  //do something here
  await sleep(5000) //wait 5 seconds
  //continue on...
}

Example 2: sleeping in js

function sleep(milliseconds) {
  var start = new Date().getTime();
  for (var i = 0; i < 1e7; i++) {
    if ((new Date().getTime() - start) > milliseconds){
      break;
    }
  }
}

//using sleep()
sleep(2000); //sleep for 2 seconds