There is no doubt that you get more visual information from looking directly at ‘reality’ than you do
from looking at a photograph (of reality), but it doesn't necessarily follow that to paint from life is better -doesnt it depend a bit on the subject matter and if you can feasibly stand in front of it to and paint it? or are we all budding impressionists and paint only the outdoors?
A photograph as a visual aid can be helpful, as is drawing from life an essential part of learning to draw, as is using your imagination but ultimately the quality of outcome depends entirely on the artist. There are many excellent artists who painted exclusively from photos or just painted ‘photos’, (think photorealists) and many great artists who never did as the camera had yet to be invented and yet their interpretations had little to do with a ‘real’ external reality…Titian,Rubens etc. but they were trained in life drawing.. and then there are realists who only painted what they saw Freud,Chardin.
I think the point is to make art as good as you can in whatever way you can by whatever means and if a photo helps then use it…(copyright issues notwithstanding)
Above is a recent work I painted from a photograph.