While I was in school, the documentary I made for my beginning production class took me about 40 hours to edit. That doesn't count driving to Idaho and filming for a day. Titled A Shear Gem, it runs less than six minutes.
I think of what Mark Twain said, "If I'd had more time, I'd have written a shorter letter."
Quality, and filming, takes time.
I shared this last year, but just for fun, here's my documentary short again: