SagaciousThink - Global Operations Excellence
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SagaciousThinking Blog

Musings from the team.

Assumed to be True

Everyone’s done it; they’ve made an assumption only to feel the disappointment when reality does not comply by following the plan.  Or, at least I am assuming that to be so, as I have certainly made some spectacularly bad assumptions – “I’ll have plenty of time to make my connection at Heathrow” or “we’ll get clearly defined requirements back from the end user” or well, you get the idea.  A Google search for “never assume quotes” yielded over two million hits, so many other individuals have shared the pain of erroneous assumptions Yet we continue to make them, and the problem is not that we make them, but its that we fail to validate them, and in our mind they become facts and are treated as such. 

Planning ahead

Everyone has their own approach to laying out project details; there’s a certain comfort with repeatability and ensuring the details are captured.  What is included in these activities, conscious or not, is the incorporation of assumptions, such as: 

  • The work will look like this
  • My staff can perform this amount of work during a given amount of time
  • These requirements must be followed to comply with the permitting authorities
  • The clients purchased that amount in the past so we should expect more of the same.
  • We should expect these working conditions
  • The competition will respond this way
  • Only these risks should impact my project 

There’s no avoiding making assumption because the very nature of planning requires looking into the future and making educated guesses as to what will happen, who will be involved or impacted, what outside forces might require a chance in course.

But how often do we confirm or validate these assumptions?  An assumption, after all, is an educated guess, an acceptance that something is true, or certain, without proof.

Not Enough 

Too often those assumptions become facts in the minds of the team and are never confirmed.  They drive behaviors and may lead to miss opportunity. Repeatedly.  Compounding this problem is that many organizations are fond of reusing templates and rules from previous efforts without confirm that they have current and valid material. Consequently, faulty assumptions could yield chronic sub-optimal results.  Some simple actions can be taken to avoid missteps.  


  • List all of the assumptions made to generate the work plan.
  • Give each assumption an “expiration date” to check in to confirm that the assumption is still valid, or identify what is fact.  It may be that the time is not right, so a new “expiration date” is required.
  • Provide as much information or context as possible supporting the assumption.  For example, if the estimated quantity of work performed is based upon permitting requirements – cite the requirements and ensure they’ve not been updated or superseded.
  • Give context about why assumptions were made so that if using information as a basis for future work, the estimators can determine if the assumptions still appear to be valid or need to be modified or discarded.
  • At the end of the project, validate all of the assumptions and identify that were erroneous and why.  Do they still make sense?  Which ones may require some more research? 

 Done repeatedly, the recommendations should improve the team’s ability to determine an effective plan. The goal is to improve the quality of assumptions by validating the ones have been made and learning what worked and what needs to be improved.