Navigate to an account record which has the standard field Type populated with a value of Prospect.
The account field Type is a standard picklist field used to record the type of account such as Prospect, Customer, Partner, and so on.
The Account page will appear with the Lightning Component AccountStatusMessage at the top of the page and display the customized message Acme is a Prospect account!, as shown in the following screenshot:
Only accounts that have the Type field set as Prospect will show the message. This is controlled by the code within the Lightning Component so that any other value for type, such as Customer, Partner, and so on will show no message.