I found this interesting post on the web. Here the author williamcaputo is trying to describe the "thinking" of "done" by the traditional team Vs Agile team.
Traditionally 'done' means "We won't have to work on that anymore - and if we do, somebody must've screwed up." For Agilists 'done' means "We have accounted for what is known. If the situations changes, we expect to revisit this work."
Thus the two approaches have different goals: One is to finish, the other is to keep pace with change.