This is a great use case, one I may implement on sas.com soon.
In this case you're looking for absence of an activity.
There are 2 events you'll need to define this segment:
- Site visitors that view form ABC
- Site visitors that submit form ABC
Then you want to target users that view form ABC and do NOT submit form ABC within X minutes or hours.
Give it a shot & let us know how it works out.