False starts happen when instead of action launching in a story, there are several scenes leading up to that action that don’t launch action, the scenes are simply there to say, Action is going to happen, so here is a scene to say action is going to happen, and another to say action is going to happen – while the action never actually happens.
Imagine two gun fighters standing in a bar, saying, Okay noon tomorrow we meet. Then noon tomorrow they meet and say, Okay, at twilight we meet. Then at twilight, they meet and say, Okay, at dawn tomorrow –
Those are false starts. Multiple scenes meeting to plan a gun fight. When it would be much cleaner and drive story more powerfully for gunfighters to simply walk onto Main Street and draw and fire.
False starts are a structural problem. Want to avoid false starts? Check out Structural Writing in Courses.