If you host your websites on a dedicated server, you would expect that they'll perform very fast and that the access speed to them will depend exclusively on the Internet connection of the visitors. However, this is not going to be the case if the server has poor network connectivity or uses a network card, which simply cannot handle high volume of traffic. If this is the case, it will take a long time for your sites to load if many people open them simultaneously or visitors may see error messages. As a result you may lose site visitors as in all probability many people won't revisit your website if they have experienced difficulties or slow loading speeds. That is why you ought to pay attention to the network components of any new server which you get and not just to the main hardware like CPU, Ram memory or hard drive.