In my book assumptions are a
constant source of risk, due to the fact that they represent something that is
unknown and hidden under a blanket of guessing. They are however easy to make,
simplifies things and offers a shortcut in situations where unknown variables
are encountered. In other words a necessary evil for most of the things we do
and when made consciously they might even serve you well. If assumptions are
injected unconsciously bad things might happen on the basis the risk you
indirectly accept.
This corresponds (more or
less) with the dictionary
definition of assumption: “Accepted cause and effect relationships, or
estimates of the existence of a fact from the known existence of other fact(s).
Although useful in providing basis for action and in creating "what if"
scenarios to simulate different realities or possible situations, assumptions
are dangerous when accepted as reality without thorough examination”
Back to the plan under
discussion the other day… With all the assumptions aired while walking through
the plan I had to ask the author about the foundation on which it was build. My
claim is that it could hardly be estimates, as many of the activities was based
on assumptions, it would have to be guesstimates, or in other words inaccurate
estimates – This argument caused quite a stir.
We ended up agreeing that the
plan was fine, but all assumptions that were related to activities on the
critical path of the project had to be documented. These assumptions had to be
proved right or dismissed with adequate re-planning as a consequence. Until
this point in time they where they were considered risks. It was hard work
identifying the assumptions, but gave a good picture on risk vs. critical path.
Conclusion: Assumptions are
not the mother of all evil but be very conscious when operating on assumptions.
You cannot avoid them, but rest assured that assumptions are the equivalence of
unmanaged risk if you are not, especially if you build critical plans on
assumptions!
Happy testing!
/Nicolai