What is a Walled Garden? And why it is the strategy of Google, Facebook and Amazon Ads platform?

The walled garden restrains advertisers from challenging the performance of the network. It is very difficult to compare the results of a campaign performance between Facebook and other marketing Networks/Tools. It is giving much less transparency about what is really happening and can lead to some errors not being detected in time. 

For example, it is well known that Facebook miscalculated their video average viewing time for 2 years without having been questioned by any other reporting tool.

If you are a publisher, the Walled Garden approach is best to monetise your inventory and data.

Building a Walled Garden means you have the power of negotiation to sell a new private Advertising Network to Advertisers. 

A Walled Garden is a closed ecosystem where the operator of the ecosystem controls all the operations. It is often the best way to have a profitable business in the maturing days of an industry.

For example:

• The 1970s telecommunication industry. At one point, only phone devices the telecoms operator manufactured could be connected to their network.
• Apple controls the iOS ecosystem by having control over iOS applications.

In the Digital Marketing field, you reached the Walled Garden level when your clients have to use your entire marketing stack to run their campaigns.