Stop Guessing and Start Planning: The Key to Managing Uncertainty with Deadline Ranges

Adam Ben Shmuel
3 min readApr 14


Uncertainty is a major challenge in project planning, but traditional management models often fail to adequately address it. This article proposes a new approach: using deadline ranges and confidence intervals to better communicate and manage uncertainty. By breaking down projects into manageable parts and setting realistic milestones, we can minimize uncertainty and ensure project success.

Introduction: The Challenge of Uncertainty in Planning

Significant uncertainty exists at the start of most of the projects (Cleden 2012). We try and overcome this uncertainty by using traditional management models that include:

  1. Risk Management by mapping possible scenarios and allocation of a certain risk score. This is usually skipped and is rarely a phase that is implemented as part of an organization’s planning proccess in a meaningful way.
  2. Agile methodology that breaks down the planned work into smaller iterations that allow improvement in planning accuracy. The implementation varies between organizations. Planning is usually according to tasks that are sized according to sprint length or according to a points mechanism for planning.
  3. Contingency Planning of possible courses of action in case certain risks realize. This tends to both create a large planning overhead, along with a usual pattern in which the main course of action is planned vigourosly, while the additional courses of action are skimmed and aren’t thoroughly thought through.

Understanding Deadline Ranges: A Key Concept

One of the reasons that planning proccesses fail is because we try and work with exact values. This doesn’t provide neccessary context that causes inacurate estimations.

An improved approach is to comunicate project completion timing via confidence intervals. For example, instead of estimating that completion of a task will take about 5 weeks, it is much better to say “I am 90% confident that the completion of the task should take between 3–8 weeks.”
Usage of a wider range adds important information regarding the uncertainty of certain tasks in comparison with others. Using ranges and confidence intervals allow better communication with upper management.

This seems odd — giving a month of variance seems like something that is impossible to work with, this is where our next section comes into play.

Milestones: Breaking Down the Project into Manageable Parts

A crucial step in planning is done by creating deadline ranges for small manageable parts. A rule of thumb would be to breakm down implementation steps to an upper threashold of 16 hours. Using task milestones requires work, but allows decision making according to implementation. If a certain task proivides high levels of uncertainty, addressing them first or discussing variance factors and performing measurments and variance mitigation. This allows for clarity and a solid basis for communication with key stakeholders.

Conclusion: Adopting Deadline Ranges for Effective Planning

Deadline ranges always existed. All uncertainties are translatable to a set of values or a range.
By using deadline ranges we create a powerful communication flow:

  1. We specify a deadline range of project completion, based on the deadline ranges of smaller project milestones.
  2. We make progress, thus minimizing uncertainty regarding the whole project’s deadline.
  3. We communicate progress by updating our project’s deadline range with a narrower range.
  4. We continue mitigating uncertainty until we may reach a concrete deadline with very high certainty.



Adam Ben Shmuel

Cloud group manager 🚀. Could talk for hours about the cloud and about management!