Why is that your internet is slower during certain "peak" times? When a company promises you 100 mbps or higher, this generally is when others are scarcely using it. The internet company sells a lot of those 100 mbps connections, but do they have enough bandwidth so that everyone gets the 100 mbps promised? No, this is called the oversubscription ratio. They are counting on the fact that everyone isn't going to be using the internet at the same time. So when they do at the peak times of day, the internet is much slower.
Traditional providers oversubscribe that 100 mbps 50x - 100x and sometimes even higher.