请问是什么原因造成的

var http = require('http');
var urls = ['http://www.runoob.com/', 'http://www.hubwiz.com/', 'http://www.saylove.com/']
function fetchPage(url) {
    http.get(url, function(res) {
        console.log("已经成功请求",url)
    })
}

for(var i = 0;i < urls.length;i++) {
    fetchPage(i)
}