How do you decide whether you should show a success message or not?

Question

I have an application where the user can perform the following actions.

• Delete a project - Followed by a confirmation
• Rename a project
• Share a project
• Remove a shared user

For those actions, as feedback I can notify the user,

• The project has been deleted
• The project has been renamed
• The project has been shared with x,y,z users
• A X user has been removed from this project

I understand that something like an error message, e.g An error message for an invalid email address - is absolutely necessary because the user can't continue their work without addressing the issue. And it will work as it should on my app.

But is a success message always necessary if they can see a change has happened? (change being: after deleting the project - the project is no longer in there.)

[Edit]

The reason why I started wondering about this is, on mobile calendars, although the user is notified an event has been created, when an event is deleted it does not tell them it has been deleted. It is the same case when a contact is deleted as well.

Answer 1

The use of a success message is highly dependent on the action performed (its nature and importance), the context of use and your intended users.

For example, when changing account settings on a website, an unobtrusive success message is shown after applying the changes. This is often necessary because the user is not able to see the difference between the before and after states since the form fields stay the same.

On the other side, deleting an item in a TODO-list application does not need any success message since the disappearance of the given item is immediately visible (visual feedback) and self-explanatory. However, there is the requirement that the mental model of the user and the actual action performed are in line. In this case, the mental model of the user is that the disappearing of a row corresponds to the complete deletion of the associated item. If you consider a TODO-list app that stores all its data in a cloud service, the disappearing of the row might not correspond to the actual deletion given network problems or unavailability. In this case, the application should indicate to the user that a request for deletion has been sent but that no acknowledgement was yet received (with an appropriate visual feedback), in order for the mental model to stay intact.

Applying this thought process to your example, here are a few questions you can ask yourself to determine the necessity of such success messages:

• What are the mental models associated with the deletion, renaming etc. actions?
• What is the importance of a given action? Modifying account settings is high on the list, but renaming a project might not be as high.
• Who are the targeted users and how are they likely to interpret the aforementioned actions?
• Where can divergences between the mental model and internal behaviour of the product can be found?

Answer 2

You should show success message depending on task is completed or not.

If user is going to delete his/her project, and if something went wrong, then how user can know if project is deleted or not? And also, after successfully deletion of project, you should know success message. So, user can be assured that project is deleted.

Hope this helps.

Answer 3

This validation is at the center of communication between a user and the interface and is very important for users to understand their actions and the consequences.

Also perhaps consider adding an "undo" function to the success message, in case the user sees this and realises they have made a mistake.

Further reading: http://designmodo.com/ux-form-validation/

Hope this helps!

Answer 4

For making the application more 'user friendly', yes, displaying success messages for every success is a good practice. When the user performs an action, they need assurance that they successfully did what they intended to do. This also adds to the overall user experience.