I have gone to many websites and have scanned many reasons why website speed is slow...

1. Too Many Ads: Ad is a lucrative prospects for monetizing websites but if is too much, it will reduce your website speed because it adds HTTP requests, which would need addition processing time. So, limiting the number of display advertisements will ensure better performance for your websites.

2. Unclean codes: Excessive white spaces, inline stylings, empty new lines and unnecessary comments can make the website stylesheet grow larger in size. You can minify, compress and reduce these codes or elements with some online tools.

3. Use A CDN Service: It would minimize the round-trip-time (RTT) and serve the requested content in a much quicker time.

4. Multiple Redirects: In case of redirects, when a user click on a URL, the webpage needs to load twice e.g from http://prexblog.com to http://www.prexblog.com to https://prexblog.com then to final destination https://www.prexblog.com. If there are many redirects, the entire process is duplicated, thereby impacting slow website loading speed.

5. JavaScript and Flash Contents: It takes time for JavaScripts and Jquery and even flash files to be loaded and executed, kindly remove them and use HTML or HTML5 for better performance.

Others are:

Bad hosting.
Unoptimized images.


This article was copied from https://www.prexblog.com/2017/10/9-common-reasons-why-your-website-speed.html

And am Happy to share here.