When you mark something that you've been assigned as done, the following things will happen:
The creator of the item will be notified to review it.
The status of the item will change to Review or Ready for review.
Once the creator reviews the item, they have two choices: they can either send it back with comments by marking it active and clarifying the request or they can agree that it is #done.
Once they determine that the item is #done, they can also tag it as a #win and/or give you a #highfive for crushing one of your team values or just doing a great job.