The authors of Write from the Beginning list the essentials of a good ending…

The authors wrote that before your story can reach a satisfactory resolution, you must first establish the problem. They give a couple of examples including this one:

A young, newly married couple are having marital problems because the wife resents her husband playing golf every Saturday afternoon when she would prefer to go to the beach.

The problem would appear to be that of the husband choosing between the beach and golf. A possible answer could be for the husband to go to the beach on alternate weekends and play golf on the others. But neither character has changed, they’ve merely come to an agreement. And that is not the real problem. What they are actually fighting about is the wife’s possessiveness and jealousy, and her inability to understand how her husband could be content to spend an afternoon without her.

A satisfactory ending would be when she realises her problem and comes to terms with it. They could still come to the same agreement, but now the problem is resolved and not just solved.  

The authors also advise to keep the whole story simple:

The less characters there are in a short story, the better. If possible, everything should be seen from the viewpoint of one person: the main character. The shorter the time span, the better.

If you hope to sell your story to a magazine, you will need a happy ending and usually an unpredictable one. Editors want strong stories containing sincere emotions and values, and strong plots.

See Write from the Beginning, All you need to know about writing the short story by Eileen Molver, Marie Thorpe and Janet Nicholson. Published by The Writing School, 1990.