Even if the user disables the tutorial it will show again with the next login.
Why does the tutorial still appear?

The information whether the Tutorial is enabled or disabled, is located in the Local Storage of the Browser.
For example if cookies are deleted in the IE, this information gets deleted as well.
On a Terminal Server this information can be lost, if the Local AppData folder is cleared after log out or if the user is on another Terminal Server after the next sign in (Terminal Server Farm).

To prevent this, save all user specified settings in the database.
Relating to this, use the following FAQ article for instructions: Where are the user-specific settings stored?