Long fiction is wonderful and you can lose yourself in it as a reader and as a writer, but short stories don't allow the same kind of immersion. Often the best stories hold you back and make you witness them. This may be one of the reasons some people reject the form. That and the fact that they are harder work to read. A story will not let you get comfortable and settle in. It is like a stool that is so small that you must always be aware of sitting.