Originally Posted by MikeDVB
If, for example, your website is 250 kilobytes on load - you can serve about 3,906,250 page loads per month [assuming no caching is in use on the client side / browser / anywhere else]. In reality you'll be able to serve more than that because you're surely going to have repeat visitors that have some of the data cached and, as such, they don't get sent the full 256 KB every time.
Not necessary if the customer doesn't have the performance requirements then he/she will be only able to service less loads and such.
It's how "100TB" and "unmetered" bandwidth (really transfer) providers sometimes works. Because they allocate "limits" that you will likely not be able to reach to any real capacity.
Now if you really paid up for a 100TB transfer server then yes you will likely be able to use up that amount. Even reputable unmetered providers will allow you to use their pipes as you need.