what are quick tasks? I have read the documentation, but cant seem to understand

In a process-backed record, quick tasks serve as the related actions for your process record.

In most cases though, the primary purpose of a quick task is to display a user input task without the task populating in your 'Tasks' list. For example, say a user wants to edit a record and so they start a related action which kicks off a process. Shortly after, they change their mind and click out of the window without making any changes. They don't want the task to show in their 'Tasks' list, because they don't care about it anymore. To account for this behavior, you can make the user input task a quick task and then set an exception timer to except out of the form and end the process so as to not leave it hanging in memory.

In a process-backed record, quick tasks serve as the related actions for your process record.

In most cases though, the primary purpose of a quick task is to display a user input task without the task populating in your 'Tasks' list. For example, say a user wants to edit a record and so they start a related action which kicks off a process. Shortly after, they change their mind and click out of the window without making any changes. They don't want the task to show in their 'Tasks' list, because they don't care about it anymore. To account for this behavior, you can make the user input task a quick task and then set an exception timer to except out of the form and end the process so as to not leave it hanging in memory.