You have the home page, the about us page, the services/products pages neatly categorized and arranged and the contact page works perfectly. Your website is ready and working just fine. You have various marketing campaigns going on pulling in visitors
But wait! Do you have these 5 web pages which

Make your visitors experience richer
Improve your site [...]

Looking for some information urgently and you land on a 404 error page - nothing can be more frustrating than that. The 404 pages are painfully for webmasters and more painful for users. The 404 page causes a dilemma for SEO’s as to what exactly should be done about the 404 pages whether they should be kept as it is or they should be or they should be redirected using 301 redirect.