I think that Ms. Fields is right in her "a favor please" message. The students now a days have a short attention span and need encouragement to work longer at a project they think is finished.
Although there are some students who you can only "encourage" to go so far.
With these students I generally have a short term assignment or extra credit project which utilizes materials we were working with. This encourages them to explore other ideas they may have come up with that didn't apply to the project they finished and couldn't use.