It's one of the simplest and most common scenes you'll find in a film: two people talking to each other. Just because it's one of the most common, doesn't mean people still don't get it "wrong," especially those who are just making a movie for the first time. You may even subconsciously feel like something is wrong, but it's possible you weren't able to put into words what felt off about the scene. Embedded below we've got a great tutorial to help with choosing the proper camera angles and framing, and why the rule of thirds can make for a more interesting and "cinematic" scene.
Thanks to Tom Antos for the video:
Obviously these are general guidelines, but these are the basic rules that govern almost any film. I know some people might take offense to having to follow by rules, but in my opinion, you can only successfully break them when you fully understand them. I think if you understand the effect that basic angles or framing have on your audience, then you'll have a far better idea of what it does to the viewer when you choose to do something different.
Understanding where you are putting the camera is just as important as the dialogue or the plot of your movie, because the language of cinema is a bit of an unspoken rule between the filmmaker and the audience, and even though the audience may not be able to articulate what you've done with a shot, if something is different from the norm, there is a good chance they'll feel it.
For those who are plenty experienced in these rules, when have you chosen to break them? What effect were you trying to achieve?