Some reflections by Nick Milton on why knowledge management within organisations is so poor. If I were him, I would have included the below illustration from gapingvoid as I think it illustrates his five points rather well.

data, information, knowledge, insight, wisdom, impact

Firstly much of the knowledge of the organisation is never codified as information.

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Secondly, a common problem (a corollary of the first) is that project knowledge may never have been recorded in project documents.

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Thirdly, and a corollary to the first two, the vast majority of project information is not knowledge anyway. If you are relying on project documents as a source of knowledge, you will be relying on a very diluted source - a lot of noise and not much signal.

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Fourthly, if there is codified knowledge in the project documents, it tends to be scattered across many documents and many projects.

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Finally, many of the knowledge problems are cultural. People are incentivised to rush on to the next job rather than to spend time reflecting on lessons, no matter how important.

Source: Why you can’t solve knowledge problems with information tools alone | Knoco Stories