Once the layout is designed and the content is created, it is very easy to rush into the publishing phase of a web site, but this is premature. Nothing is more frustrating than a site that does not work right. The amount of testing that should be performed on a site is directly related to the complexity of it. Even simple sites require some basic testing.
Testing is generally very simple, but it is also time consuming.
Fortunately, a designer gains experience through testing web sites, and it eventually becomes easier to avoid some of the basic pitfalls. This is undoubtedly the biggest mistake that beginning web developers make. After spending several weeks on the design of a web site, the developer will want to show the site to others. It is easy to develop conspiracy theories, but relax. No one sabotaged the web site.