Traffic Calming measures are something that has grown over the years, and although most drivers detest them, they do the job they were designed for.
They reduce the speed on the roads they are installed on, as well as reduce the volume of traffic on those particular roads because most drivers don't like going over them.

Speeding drivers are the biggest reason why they are implemented along with reduced speed limits on roads where you might consider higher speeds would be fine. Until drivers stay within the legal limits set for roads, there will always be more measures put in place to slow vehicles down.

This is not to annoy drivers, but more about protecting the more vulnerable.