Every story you write has its own set of laws as absolute as physics. Your world may be in the 1880s, or the 1920s. It is not just a matter of what kind of transport was commonly available, or what was served in a restaurant. Your world covers everything from fashion to technology. Nail it down. Know your world. This is where many stories fail. In maintaining consistency in the story world.
So, think about it and be aware. Everything you write fits into a larger whole and no single element must violate the rules of your creation.
This is the story’s straight jacket. When the story world is small you find you will have more choices. Also, if you don’t know your world, then you will find yourself writing clichés.
A constant factor is a variable that cannot be changed. Some are purposeful and selected by the scientist to control the experiment while others are universal and beyond the scientist’s control. If the scientist does not note the constants, then these can lead to perceptual errors in the experiment.
So too with your story world. The physical rules of your story world, both physical and social should remain constant. Your characters will be the only variables. Establishing the story world’s constants at the beginning of the story allows the reader to focus on what really matters: the story.
If you’re working on a story, then start by thinking of all the locations that feature in the story. Then against each location list the things that happen. Then add the names of characters who will be in these scenes. Now list any objects which you can see in this location. Now you have the basis for a series of scenes. Just fill in the details and use these panoramic views to stimulate your writing.