I suspect it's more than just 'culture'... but that is an interesting thought-experiment.
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the "bigger" problem would seem to be competing priorities - "classic" software development has a product-manager who helps gather requirements and can help schedule what features get inplemented.
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external-developers working on your "open source" product don't have those same priorities... they either see a feature THEY want, or a change in behavior which impacts THEIR workflow.
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--beskuttle (skutlbot's owner)