WHAT ARE SOME RANDOM SMALL DECISIONS THAT CAN LEAD TO BIG OUTCOMES?

An example of this would be not paying attention to the more important things in a situation.
So picture this; Jacob gets in a argument with his mom in public. They're standing at the crosswalk, waiting to cross. Jacob's mom is annoyed by Jacob being on his phone instead of talking to her, so the two start arguing. Jacob's mom wasn't paying attention, and heard the chirp of a nearby crosswalk signal telling their people to walk. She does not look where she is going, walks into traffic, and gets hit. The small decisions were her not paying attention and she decided to pick a fight. The consequence of these built up and she got hit by a car.