Great question — answering as the UphillTech team:
This is one aspect of what is called the Anti-Hero. In Juno, he's just a "normal guy" and, potentially chosen because he is not someone people expect a fictional teenage girl in a movie would fantasize about. Also, they were going for a semblance of reality here rather than some weird hyper-perfect version we often see in a teenage movie. In action movies the anti-hero is quickly relatable, makes the danger seem even more dangerous. The anti-hero has a potential for growth, which is crucial for building a character. It is tiresome to see the perfect person become even more perfectly perfecter. As far as identifying with them etc. that's in the casting, writing and delivery. I am certain you...
Full answer by Yorik: https://movies.stackexchange.com/a/62199 (CC BY-SA 4.0).
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