Trouble shooting infinite loop

getElementsByClassname.js

var getElementsByClassName = function(className){
  // Array of document element
  var elementList = Array.prototype.slice.call(
    document.body.querySelectorAll('*')
  );

  var results = [];
  var count = elementList.length;

  // check body independently since the above array doesn't contain 'body'
  if (document.body.className === className) results.push(document.body);

  // why doesn't the recursion trigger this countdown?
  count -= 1;
  if (count === 0) {
    return results;
  } else {
    if(elementList[count].className === className){
      results.push(elementList[count]);
    }
    getElementsByClassName(className);
  }
};