Vivian Maier also, like Winogrand, left behind a vast amount of unprocessed (and nearly destroyed) film. It is now being developed and scanned after her death.
This also brings to mind another interesting point. Usually photographers themselves decide what their best or most desirable work is, and print and exhibit it accordingly. If your film is processed after your death, then someone else's view of your best latent work is being showcased to the public. Imagine walking through an exhibition of your photographs, but never having seen most of them before! ... Especially years hence, when most of your memories of taking those particular shots have faded from your mind.