Someone has quoted a statistic out of context. A single statistic such as this is the best versus the worst individual on a given day with a given technology assignment, etc.. That's like hiring someone straight out of college and having them compete against Don Box on a COM project. Yeah, there would be a 28-1 difference, but that is a shortcoming of the organization and not the individuals. And a factor of 28 is HUGE.
Other facts that are similar (and more applicable) are:
- Best people in general outperform the worst people in general 10:1. Hopefully your organization does not employ the "worst" group, so your statistic might be lower.
- The Best performer is about 2.5 times as productive as a median performer (median is the point at which 50% of the number of developers are above, and 50% are below).
- The 50% that are above the median are 2:1 as productive as the 50% below the median.
[From DeMarco and Lister's Peopleware, p.45]
The last statistic is the most important since almost all significant projects require teams to finish in any reasonable amount of time. But still, there are no tools or other "silver bullets" out there that will as easily double the productivity of your organization. This is one of the primary reasons why PEOPLE are consistently one of the most important contributors to project success in the Standish Group's CHAOS report.
I have seen another statistic from one of my Software Eng textbooks - 20% of team carries 80% of the effort required.. (called the 'Pareto Principal').. The trick is to keep the 20% in tune & happy..