Computer will not sync video to iPhone?

I converted lost season 2 the first 3 episodes from avi to mp4 and dragged them into iTunes. I connected my iPhone and it showed up and everything. I clicked on it and check the 3 videos I want to sync. I press apply and it syncs and everything but then when it's over it didn't show up on the iPhone. Did I do anything wrong?

How did you convert? I'm assuming that when you click on "movies" in iTunes, you see the files - right?

Anyway, I never sync. When I wanted music or video on my iPod, I just checked the "manually manage" box on iTunes and just dragged and drop the files onto the iPhone tab on iTunes (yes, even iPhone 5 and itunes 11).