It’s all about the story! Sure, some might be able to meet their point quicker than others (The Nearly Departed) while others take pleasure in that slow build, escalating the tension and dread until it can’t be withstood any longer. The only requirement for a short story (and it’s a loose one at that) is that it comes out approximately around or less than novella length. So, typically they’ll max out around 50,000 words or so, with a little wiggle room of course.