How quickly a site shall open depends not just on the Internet connection of the visitor, but also on the connectivity of the hosting server where the website is hosted and on the network infrastructure - routers, server network card, and many others. Slow connection or hardware that is unable to cope with a high volume of inbound and outgoing traffic can have strong impact on the user experience of your customers and the efficiency of your site as people will most likely see error messages that the website isn't available or it will take a long time for your content to load. If this kind of a thing takes place, it's unlikely that the site visitors will revisit the website. That is why you should always examine the connectivity of any hosting server that you obtain and not only the main hardware components which include hard disk drive, central processing unit and physical memory.