One source for the 10x number is the book Peopleware. They did Coding War Games where developer got an exercise. The 10x is the time it took them to code an application which fulfills the requirements. The best is 2.5x compared to average.
Since it is a single person task, they cannot impact anyone negatively.
However, the most interesting fact in my opinion is that within the same organization the difference is only 0.3x. Either the organizational environment determines your productivity or the organization determines which kind of developers get there. The experiment does not tell us anything how the productivity of a developer changes when he changes organizations.
Since it is a single person task, they cannot impact anyone negatively.
However, the most interesting fact in my opinion is that within the same organization the difference is only 0.3x. Either the organizational environment determines your productivity or the organization determines which kind of developers get there. The experiment does not tell us anything how the productivity of a developer changes when he changes organizations.