Productivity in software development isn’t controlled just by the individual, it is controlled by how several individuals interact with each other.
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Yes, individual programming skill matters greatly. So does the ability to work effectively with others. It’s not either or, it’s both. And that’s still not enough. To be productive, programmers need a supportive environment, and I don’t mean (just) nice colleagues. I’m talking about being in an organization designed to maximize the effectiveness of those who work in it.
via tobiasfors.se
and from the comments, Bob Marshall/ Deming:
“some 95% of an individual’s contribution is a function of the system that they have to work within, and only some 5% is down to an individual’s innate talent and effort”