Are 20% of files responsible for 80% of defects?
Neil Walkinshaw, Leandro Lei Minku · 2018
Background: Over the past two decades a mixture of anecdote from the industry and empirical studies from academia have suggested that the 80:20 rule (otherwise known as the Pareto Principle) applies to the relationship between source code files and the number of defects in the system: a small minority of files (roughly 20%) are responsible for a majority of defects (roughly 80%).