Why does it seem that projects always take longer than we anticipate?
Because they typically do.
Leaders generally underestimate the time it will take to complete any complex task. They fail to account for the challenges and obstacles inherent in completing large or elaborate projects, preferring instead to remain optimistic about what could be achieved in the allotted time. Unfortunately, far too often their optimism shines brightly until reality snuffs out the light.
Underestimating the time and resources it takes to complete a project, known as the Planning Fallacy, is a common bias that inflicts almost everyone at one time or another. This bias can be both costly and wasteful as deadlines are shattered and budgets expanded to meet the project goals.
Avoiding the propensity to plan optimistically is essential work for good leaders. They prefer to underpromise and overdeliver, not exceed budgets and timelines.
Simply being more realistic and using previous projects as a guide is not enough to offset this fallacy. Good leaders go out of their way in the planning process to brainstorm the potential obstacles and challenges that may derail execution. Doing so with a team helps everyone to combat this bias in their own project planning.
Smart leaders also put contingency plans in place in the event that a project requires more time and resources. Knowing precisely how the team will handle missed deadlines and cost overrides not only prepares for the worst, but also drives home the point about the consequences of being unrealistic. Whereas contingency plans on minor projects will likely condone poor planning, it is foolhardy not to have them in place when blowing the end result can be catastrophic.
When it comes to underestimating what it takes to complete a complicated project, never undervalue the power of brainstorming what can get in the way.
We took a few minutes to discuss the Planning Fallacy together: https://twitter.com/i/spaces/1YqKDoEnbzoxV
Re: Deadlines - I think we sometimes put undue pressure on ourselves and set self-imposed deadlines when they aren't really needed. I've found (I've actually measured this) that people care less about meeting a deadline and more about regular communication about progress. I did a study for a Facilities Department where I tried to identify key drivers of customer satisfaction on Facilities Services requests (N ~ 12,000 requests). The #1 predictor of customer satisfaction was not 'the request was completed on-time' but 'the Service Tech provided frequent updates to me on the progress and completion of my request'. Like the Admired Leadership behavior - Frequency, Not Quality, Deepens Relationships Most.