If you have set a work item to repeat on a recurring schedule, future work items will be created automatically containing some information from the previous work item in the schedule.
Data that is carried across includes:
Tasks
Task descriptions
File uploaded to the task descriptions
Work item description
Time estimates
Budget
However, there is an exception to these rules. If you are using Tasklist Automators to control task assignments and/or task due dates, then those Tasks will not be copied from previous work item. Instead, they will be created blank, and updated when the Automator is triggered.