In case you host your sites on a dedicated hosting server, you would expect that they shall perform very fast and that the access speed to them will depend solely on the Internet connection of the visitors. Nevertheless, this will not be the case in the event that the hosting server has bad network connectivity or relies on a network card, which simply can't deal with high volume of traffic. If this is the case, it shall take quite a long time for your internet sites to load if many people open them at the same time or visitors might even see error messages. Because of that you might lose site visitors as most likely many people will never revisit your site if they have experienced problems or slow loading speeds. This is why you need to pay attention to the network components of any new server you purchase and not only to the main hardware such as CPU, Ram memory or hard disk.