It doesn?t work because …
… when you provide a service, people will buy from you when they know and trust you. This is because when you sell a service, you can?t show it to people as you can with a product. You can?t show people what colour it is and how big it is; you can?t compare it to your competitor?s products. Quite often, you?ll be asking clients to pay you before you even start working with them. You?ll be persuading them to invest in you long before you create any results for them.
So this means that before someone buys from you, they need to get to know you and trust that you can deliver what you promise. Can someone build up that level of trust with just a phone call? Can you, or a telesales specialist persuade someone that you or they have never met, to part with their hard earned cash and give it to you? Can you (or they) sell something you can?t see, to someone who might not even be looking for your service?
For service businesses, telesales does not work.

It does work because …
… when you?re selling a product or promoting an event, you have something tangible that people can see and touch. If you?re selling products, you can actually show them to people. You can show them the cover of the book and some of the content. If you?re running an event like a workshop, you can show potential customers the material that you?re going to use. Because the event has a date, people can make decisions about whether or not they are free that day and how much time they want to spend out of their office.
Buying a product or booking a place at an event is transactional ? it?s a one off decision and it?s a relatively easy decision to make. It?s not like investing in an ongoing service with monthly payments.

For service businesses selling products and events, telesales does work.