Missing element in array

I'm new to Node.js. I'm using zombie.js to scrape a web page title from a few websites. Below is my code:

var Browser = require("zombie");
var util = require("util");
halt = require('delayed');
title = [];
url = [ 'http://www.apple.com', 'http://www.microsoft.com', 'http://www.dell.com' ];


function getTitles(url){
    //console.log('Start scraping title');
    var length = url.length;
    console.log('Total Site to Scrape: '+length);
    label = 1;
    for(var i=0;i<length;i++){
        browser = new Browser()
        browser.runScripts = false
        browser.setMaxListeners(0);
        browser.visit(url[i], function(e, browser, status, errors) {
        browser.wait(function(){
            title[i] = browser.text('html > head > title');
            console.log(label+': '+title[i]);
            browser.close();
            label++;
        });
        });
    };  
}


getTitles(url);

halt.delay(function () {
    console.log('Array Length: '+title.length)
    console.log('Array Content: '+title)
}, 10)

Below is the output of the code:

Total Site to Scrape: 3
1: Apple
2: Dell Official Site - The Power To Do More | Dell
3: Microsoft Home Page | Devices and Services
Array Length: 4
Array Content: ,,,Microsoft Home Page | Devices and Services

The part that I don't understand:

1. Why is the array length returned 4 instead of 3? There are only three urls
2. Why is the array content only return the last element? Where are the other two missing elements?