Are You Making These Assumption Mistakes?

Funny things can happen when we make assumptions. Grab a cup of coffee and let me share a story about me, my twin brother Charles, and our wonderful wives.

Harry and Charles Hall - The Twins

The Twins – Harry and Charles Hall

One evening, I took my wife Sherri out for dinner. We had a wonderful meal at Giuseppi’s. Sherri told me that she wanted to run by Ace Hardware to pick up a gift for Charles’ wife, Kelley.

While we were at Ace, Sherri called Charles to ask him a question concerning the gift. Charles happened to mention that he and Kelley were out for dinner. Sherri asked where they were eating. He said, “Giuseppi’s.”

Sherri said, “We were just there. Where are you sitting?” Charles told her near the bar. Sherri followed up with a more precise question, “Which booth?” Charles replied.

Sherri laughed and said, “You guys are sitting exactly where we were just a few minutes ago.” Charles said, “So…that’s why the waitress looked at me so funny!” I drove back to the restaurant to explain to the waitress – I didn’t want her to make a wrong assumption.

“What’s great about comedy, obviously, is that you set up a situation that people assume one thing and then you break the assumption. That’s basically the backbone to comedy. You set up a situation, let people make an assumption, and then you break the assumption.” -Bryan Cranston

Assumptions are great for comedy, but assumptions can be killers in business. Invalid assumptions can lead to budget problems, schedule delays, and resource problems, to name a few.

Individuals and teams make assumptions when planning or making decisions. As we consider different options, we choose the path that we believe will bring the greatest success. However, our plans and decisions are sometimes based on faulty assumptions. Let’s explore common mistakes and what we can do about each.

Assumption Mistakes

  • Failure to identify assumptions. Individuals and teams often make assumptions in subtle ways – they are not even recognized as such. When you hear or perceive an assumption being made, restate the assumption allowing everyone to hear the statement clearly. If you have an assumption register for a project or program, capture the assumption.
  • Failure to check assumptions. Explore the validity of the assumption. Is the assumption accurate? Is it consistent with facts? Is the assumption complete? Where did the information come from? Is the source valid?
  • Failure to assess assumptions. Dr. David Hillson, the Risk Doctor, says, “…not all assumptions matter equally…some assumptions might prove false.” Dr. Hillson recommends the use of an IF/THEN test: “IF this assumption proved to be false, THEN the effect on the project would be…” The IF statement reflects probability and how likely the assumption is to be unsafe. The THEN phrase is about the impact or the significance. Record risks in your risk register where appropriate.
  • Failure to find alternative options. Assumptions are a way of dealing with uncertainty when we have different options. Are there other options that may reduce our risks?
My brother Charles is a Certified Public Accountant (CPA). He blogs at cpa-scribo.com. Great stuff – check him out!

Please note: I reserve the right to delete comments that are offensive or off-topic.

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