Pareto Principle or Pareto Rule is quite fascinating in managing personal and professional life, time management, task management, self motivation etc. Crux is if you focus few vital issues in life you manage major part of your life better. The same applies in profession, organization, department function, and activity too. Only thing is it is to be applied objectively, and smartly.
Let us see how it can work in terms of software testing and quality control:
80% of software quality is maintained by 20% of programmers
80% of bugs in an application are written by 20% of developers
80% of bugs are fixed in 20% of time
20% of a business application accounts for 80% of bugs