There is a lot of expectations from the internet with providers telling you they have the fastest system. What they fail to tell you is that you probably will never get even near the maximum speed they quote and I will tell you why. They are not lying but they are somewhat economical with the reality.
When you connect to any site you are going through a significant number of switches in the network. The fastest speed you will ever get is the slowest speed of any link within the system. The providers may upgrade their network to be super fast, but unfortunately the rest of the world doesn't do that.
If you want an analogue analogy consider pouring water through a pipe. A 6" pipe will get the water through a lot faster than a 1" pipe. It is the same with networks. You will only be as fast as the slowest portion on the network that you connect through.
I know some people here will say they have had really fast connections and I am sure they have but connect to the same site the next day and it be be akin to a snail. Each time you connect you are not necessarily going to use the same route and even if you are the use by others of that route will vary.