Quality Quote: Without Data, You're Just an Opinion

Today’s quality quote is commonly attributed to William Edwards Deming, although it does not appear in his books and its origin is unconfirmed: “Without data, you are just another person with an opinion.”

Related guide: Nonconformance and corrective action, on turning data into decisions.

This statement is so true. Quantitative data is key to measuring performance against established quality objectives and determining the effectiveness of an organisation’s ISO 9001 quality management system.

But the reverse is also true, as set out in this article: “Without an opinion, you’re just another person with data.”

With the abundance of data in some sectors (big data, for example), without a system for interpreting it, undertaking statistical analysis to identify trends and drawing conclusions, you cannot form an opinion and all you have is the data. The point: you need both data and opinion.

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More quality quotes

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Be a yardstick of quality. Some people aren’t used to an environment where excellence is expected. Steve Jobs.

Those who do not learn history are doomed to repeat it

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“We can change the conditions under which humans work” (James Reason)

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“Give Your People Better Processes and Get Better Performance From Your People”

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“Under conditions of complexity, checklists are required for success” (Atul Gawande)

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Often Credited to Aristotle

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General guidance only. This article is general information, not legal, financial, safety or compliance advice, and it does not take account of your specific circumstances. Streamline ISO Consultants are ISO management-system consultants, not lawyers or licensed advisers. Standards, laws and regulator guidance change, and details were correct only at the time of writing. Always seek professional advice before acting. See our full Disclaimer.