For someone who spends his time ghostwriting books, I prefer writing short stories when I do my own writing. I always have. The two that gave me the bug were A Clean Well Lighted Place by Hemingway and A&P by Updike.
These may be cliche choices, but I was in eighth grade, maybe ninth, so they came as they came.
The downside of this is that literary journals don't publish short stories like these, or like Grace Paley's or Raymond Carver's all hat often if at all. Instead, there are numerous slow starters that never seem to develop or catch my interest.
Generally this is because they fail to make a promise to me at the beginning that it's worth reading through their leaden intros to get to the meat of their story. Perhaps there is no meat. That's why if there's no promise, I flip to the next story.
The need to make a big promise to the reader at the beginning is true of novels. You need a strong start to let the reader know there is a worthwhile story coming.
The best means to do this, is to establish what's at stake. This is not the only way (see Cannery Row by Steinbeck), but it's a good way.
And when writing short, even just a sketch, there needs to be something at stake. If the story is about a couple in a cafe leaning over a table talking quietly, they should be breaking up, meeting for the first time, discussing her pregnancy, planning a crime, etc. The issue doesn't have too be resolved, but there needs to be a reason why you are telling the reader this story or presenting this sketch.