more about conflict

I've been using my checklist system for the last few scenes I've worked on, and have been finding incredibly helpful. Even for scenes that aren't a struggle to write, taking a few minutes to go through the checklist and answer the questions seems to give me a better, more organic "feel" for what's going on between the characters and where things need to go.
After I'd applied the checklist to three different scenes, I noticed that a couple of amendments are in order. The first has to do with conflict, since only one of the three scenes I "checklisted" actually fit my definition of conflict. I assumed conflict usually comes from characters clashing over competing wants or needs, as in the example of the guy who wants bus change getting in a fight with a coffee shop owner.
One story I'm working on has where a group of characters are meeting to discuss how they're going to solve a crime, though. They don't have competing wants or needs because they all want the same thing: to solve the crime. Instead, the characters are in conflict with whoever committed the crime, a person who isn't present in the scene.
In another story I have a scene with only one character in it. Is there conflict? Yes! He's in conflict with himself as he tries to rationalize his own behavior, so he has competing wants and needs within himself. Internal conflict, in other words. Thinking it over, I realized that it's this internal conflict that makes a scene interesting (to me, anyway). It gives a sense of depth that you can't get from external conflict alone.
In the example of the guy arguing with the coffee shop owner, we could say that the main character is really yelling at the coffee guy because he's mad at himself for leaving things 'til the last minute. Like most of us, he finds it much easier to blame the other guy for being such a jerk than to face up to his inner motivations.
Maybe his leaving things to the last minute is a form of self sabotage. He might not really want to go on that date because he's still in love with his ex. Or perhaps he's late meeting his parole office because he doesn't trust himself or feel equipped to deal with life "on the outside." By adding the internal conflict he suddenly seems more real and interesting than if he was just some guy yelling in a coffee shop.
So going back to the checklist, I think it's useful to think about what kind of conflict your scene has, and not just whether or not your scene has any. And maybe ask yourself if it could be made even more interesting by adding internal conflict to an externally focused scene--or vice versa.
Next post, I'll talk about the other amendment I want to make to my checklist: Purpose.