Have you ever visited a site that worked very slowly? You click on a page and wait for it to load after 10 or worse 30 seconds of wait you find you that it was the wrong page and you now have to wait another eternity for next page. Imagine if you are the owner of such a site and your website visitors had to put up with this. If you host website on a slow shared hosting server it could end up being your site. If 10 or 30 second per page doesn’t sound much you can multiply it by number of visitors to your site and you can find out total time wasted of different visitors. It is bad for image of your site and more recently there have been several changes in search engine algorithm. One of the major changes is to put more emphasis on web site’s ability to serve pages quickly. Sites that serve pages quickly will get to rank in search engines better. When looking for shared hosting it is important to keep these things in mind and not go after the lowest price hosting. If a vendor has two, three or more hosting plans, avoid the bottom tier as it could be located on a crowded sever. Hosting service providers host between hundreds and thousands sites on a single server. These sites often run as same user on the base operating system. A website that is getting more frequent requests for pages will end up taking priority and eating up valuable resources. To avoid this looking for hosting plans that restrict bandwidth, disk space or number of active processes for its hosting accounts.
It’s acceptable to start out with shared hosting account but you should always be looking to beef up resources with a VPS sever when you are financially able to do so.