In case you host your sites on a dedicated hosting machine, you would expect that they shall perform ultra fast and that the access speed to them shall depend only on the Internet connection of the visitors. However, this will not be the case if the server has poor network connectivity or employs a network card, which simply just can't handle high volume of traffic. If this is the case, it'll take quite a long time for your internet sites to load if lots of people open them at the same time or visitors could see error messages. Because of this you could lose site visitors as probably many people will not revisit your website if they have experienced difficulties 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 which includes CPU, Ram memory or hard disk.