JSFiddle - React, Tailwind, and code Playground

HTML

<body ng-app='myApp'>
    <div ng-controller='MyCtrl'>
    </div>
</body>

JavaScript

var app = angular.module('myApp', []);
app.controller('MyCtrl', function($scope, $q, $timeout) { 
   var temp = $q.when({});
   var arr = [3, 2, 1];
   
    arr.forEach(function(element) {
        //function declaration rather than call?
        temp = temp.then(function(){
            delay(element);
        });
    })
    function delay(timing) {
        var deferred = $q.defer();
        console.log('starting: ' + timing)
        $timeout(function() {
            console.log('ending: ' + timing);
            deferred.resolve(timing);
        }, timing * 1000);
        return deferred.promise;
    }
});