This rule applied for every first-time occurrence of each new mistake you made.

FORBES: Good Employees Make Mistakes. Great Leaders Allow Them To.

So were breaking nuts open with a hammer (which could be done in four different ways, each with its own pattern of occurrence among the sites), and picking marrow out of the bones of hunted animals using a tool.

ECONOMIST: Chimpanzee behaviour: Culture club | The

The Monte Carlo gamblers invented all sorts of reasons to explain the long run of black, failing to appreciate that each appearance of black was a random occurrence.

FORBES: The Hot Hand Fallacy

The result is that each entry is an individual history of the word, from its earliest known occurrence throughout its lifespan in American English.

WHITEHOUSE: A to Zydeco: Saving the Diversity of American English