H.W. Heinrich changed the world of safety fundamentals forever with his pioneering work in the 1930s. One of his concepts that continues to make me think is his accident triangle (pyramid) - for every 300 unsafe acts there are 29 minor injuries and one major injury.
It's the concept that we all are familiar with. So many near misses lead to an analogous number of first aid injuries and onward through the logic to recordables and ending in the inevitability of a fatality.