My camera does not lie

Is this the defination for documentary? We always confused what is short film and documentary. On last monday KSFM screening theme as Malaysian Documentary the audience asked this question. Comparing to last week, this malaysian documentary isnot too crowed and the documentary screened is not too many. I watched the "not far from there" second time, the junior stared at me, and like asking the question by his eye"how come you can tahan this dunno what docu second time?" I admit that the vioceover and the music is good in my own opinion. The visual is not that perfect, too handy cam. "hometown" giving me a feeliong that too "light". Maybe is good or maybe is bad, i canot feel the sadness of the director of her lost old hometown. Maybe she intense to put a not so sad mood. So the visual is nice. The "Railway steps", the funiest one in the list. I just wonder hwo they comeup with this idea, Is they want to do soemthing for thier life or they purposely want to do a documentary then came out with this ideas? "The ground i stand" was the works for singapore art museum, is not bad but it was too handy too. U even can seen the hand to adjust the camera. It's what we can do with inde docu as a amateur? Handy cam and shaked camera to show that the picture is real and "documentary"? Now the last two from my junior, "The Highland Tale" and " It's my life", the two directors had been asked a lot of questions untill, i believed themselves were blur to answer such question. But, the main thing is, Why we choose the subject matter as our documentary content? Why, i think this question is important to make a documentary. Hm, questions is good for them to learn more, i think, i need it also.
So now i am thinking of my own documentary, but obviously, u sure know why a director want to docu his hometown right?