Phone rings (Tring tring, tring tring, tring tring...)
A voice: Hello! Welcome to abc company. We are happy to help you! To speak to an agent press 1, to know the status of your query press 2, to lodge a complaint press 3, to return to the main menu press *
Customer (Presses 1) and waits patiently for an agent to answer, meanwhile the music keeps playing and in between there is a promotional message about a product or a service.
We all have had similar experience. The reason could have been different for all of us, but we have been on the other side of that telephone call. You dial a number, a computerised voice greets you and gives you a whole list of options to pick from and do accordingly.