When you work for someone, they place deadlines for certain reasons. They can't wait forever for a final piece to be designed. And also, they would design it themselves if they had the skills to (That's why they give you the job in the first place) therefore you work for them, but on their time they expect you to finish the work for them. That's why deadlines for me would be complicated, because I'd want to work on it for myself and not for anyone else. I like enjoying my own work. And I like people enjoying it also. But I don't work on anyone's terms but my own.