Tasks enable you to organise your workflow in a controlled and trackable manner.
At least one task must be added to an order as an action. For example, Deliver to Customer is a task that sits inside an order. If that task fails, it can be rescheduled for redelivery or collection. If it is subsequently completed, the full history of the failed delivery and reattempted successful delivery is stored within the one order, giving a full history for that parcel.

Read more about tasks here: