Sorry for the brief answers but...
Is it a way to learn?
Definitely.
Is it its own artform?
Yes.
Is it subculture?
Not really.
Is it a way to prove your self and other people that "yes, I'm capable of making a feature... give me the money! ..please.."
Most if not all feature directors/film-makers start out by making shorts.
From my experience the average person on the street will turn their nose up at short films.
That's why there is very little platform for them. Shorts are mainly found on would-be directors showreels or at specialist film festivals.



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