Verification or Validation

In some recent discussions with product development neophytes, we have heard a merging of the concepts of verification and validation.  Let us set the record straight.  Verification and Validation are not synonymous.  The World English Dictionary defines verification as “establishment of the correctness of a theory, fact, etc…”   and validation as “to confirm or corroborate”.  We can thank Barry Boehm (famed American Software Engineer) for the clarifying of these words as they apply to product development.

  • ·         Validation: Are we building the right product?
  • ·         Verification: Are we building the product right?

These two things are not one and the same thing, and in the world of product development, articulating these ideas correctly matters.  Let’s look into each of these closer.

In the definition of verification, the word correctness appears. Are we building the product right (or correctly)?  It is interesting that this word does not appear in the definition of validation.  The notion of correctness is important in that it clearly articulates the scope of verification activities.   Verification is measureable, as is correctness.  Correctness requires a foundational baseline, not subject to opinion. So does verification.  Correctness is black and white.  So should be verification. 

Validation on the other hand does not contain the notion of “correctness”.  Instead it emphasizes agreement or corroboration.  In the case of Boehm’s observation, “are we building or creating the right thing?”  Validation is about achieving agreement from the customer, that their opinion of the product matches your own.  Validation, therefore, is an opinion-driven or softer exercise – not driven by fact but by perspective and opinion, and opinions can change.  In the context of a project, the fluctuating and nebulous nature of customer opinion can create scope creep, poorly defined product requirements or poorly perceived project deliveries if validation activities are not continuous and consistent.  

With these definitions in mind, it is clear that validation must be treated as an on-going and continuous effort throughout the project lifecycle in order to ensure a well-received product.  However, it may not be so clear that so too is it for the verification activities during product development.  We have shown some of the reasons in previous blogs and will discuss at length in future blogs when we turn toward verification in more detail.

How do you ensure a well-received product?

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