Recently, I've been pondering how people discuss verifying assumptions during planning, such as pricing, demand, and hiring. These are typically documented because everyone recognizes them as assumptions. However, I question whether these are truly the assumptions that cause the most complications. Often, the bigger issues stem from assumptions people aren't even aware they are making.
Picture a company preparing for a continuously growing market. A major customer segment has been steadily purchasing for years. Everyone presumes this trend will stay the same, but no one records the reasoning behind it. It simply feels natural. No one clearly says, "We assume this customer group will keep buying at the same rate." Since it wasn't explicitly mentioned, it wasn't discussed.
Months later, these customers reduce their purchases, making the original plan ineffective. People sift through data to identify what changed, but the initial assumption was never documented. It remained an unspoken understanding shared by all. Consequently, no one verified it, discussed potential impacts if it changed, or paid particular attention to it, since it wasn't formally acknowledged as an assumption. The lack of an explicit trigger meant the belief was never openly addressed.
This situation probably happens more frequently than you may think (I see it all the time). People often focus on examining the assumptions they've documented and questioning their validity. While this is important, the greater blind spot isn't necessarily the assumptions that proved false. Sometimes, it's the assumptions that the plan never even considered in the first place.
All plans include written assumptions, but many implicit ones are assumed to be obvious. However, they might be just as important since no one is paying attention to them.
Before finalizing any plan, it’s important not only to identify risky assumptions but also to ask, "What are we secretly assuming?" Someone must reveal these unstated assumptions before the plan is finalized. This ensures there's a tangible reference point to revisit later, instead of discovering halfway through the year that everyone depended on an unspoken assumption that was never documented.
