Ben Shneiderman explains design dialogs with the following: "Sequences of actions should be organized into groups with a beginning, middle and end. Informative feedback at the completion of a group of actions gives operators the satisfaction of accomplishment, a sense of relief, a signal to drop contingency plans from their minds, and an indicator to prepare for the next group of actions."
Schneiderman is explaining the process of moving the user smoothly through the various steps of an interface, making it easy for them to understand what they are doing and preventing confusion. These notifications provide the user with closure, giving them the satisfaction that the task is complete. Example scenarios include booking a flight, purchasing an item on an ecommerce shop, or posting a photo on Instagram. The user is guided through the process which steers them to their goal and feedback is delivered after each step. These include displaying notification messages or the use of other mechanisms in the interface. These can include the use of Wizards and Steps Left design patterns.
Wizards break down tasks into steps and then displays where in the process the user is. They are handy when there are many tasks involved and especially if the user needs guidance. The Steps Left pattern is similar to a Wizard, but appropriate for a simpler series of steps. Once the user has closure from completing their task, it is helpful to provide them with cues to proceed. For instance, if they signed up for an account, they could be guided into adding a profile photo and more information. ecommerce shoppers that have completed a purchase can receive a displayed prompt to continue shopping and are presented with products related to their purchase.
The use of these systems will give the user a great sense of control and closure, and contribute to a great overall experience.