Stop Expediting: One Priority System That Protects the Delivery Date

Kishore Sengupta, Tarek Abdel-Hamid, and Luk Van Wassenhove tested hundreds of experienced project managers in realistic software-project simulations. The veterans produced higher costs, more defects, and more missed deadlines than the simulation expected of seasoned people. The researchers called it the experience trap.

Past success creates patterns. Those patterns harden into overconfidence. The more experience we accumulate, the more we trust the approaches that once worked—even when the current project no longer matches the old conditions. Change efforts expose this most clearly. Successful managers already believe they have the answer. They need an external signal that forces them to question it before the damage is locked in.

That signal is the buffer burn ratio—also called the risk ratio.

Progress is measured by the ratio of remaining work to remaining buffer. A project with 100% of the work still open and 100% of the buffer still available is at 1:1 and on schedule. A project with 80% of the work remaining and only 40% of the buffer left is already at elevated risk. The ratio tells you the truth while there is still time to act.

When tasks slip, they consume buffer. Ranking tasks by their individual burn ratios shows the project manager exactly where to intervene right now. Effort applied to the highest-ratio tasks moves the whole project forward. Lower-ratio work can wait.

The same logic scales to the shop floor. Multiple priority systems—ERP due dates, managerial hot lists, rush and super-rush labels—lead to constant expediting, task-switching, and finger-pointing. No one can agree on what is truly urgent because there is no single definition of urgency.

A single transparent priority system solves that. Every order is scored by its risk ratio (buffer remaining divided by work remaining). Lower ratios mean higher delivery risk. Orders are then color-coded:

• Black: zero buffer remaining

• Red: ratio under 1

• Yellow: ratio between 1 and 1.5

• Green: ratio above 1.5

Black outranks red. Red outranks yellow. Yellow outranks green. Within the same color, the supervisor sequences work for flow. The priority list is recalculated as conditions change, so the ranking stays current.

This approach does three things at once. It identifies the tasks most likely to miss the delivery date while there is still room to recover. It adapts automatically as upstream variation or new demand appears. And it replaces intuition and edict with a clear numerical ranking that everyone can see.

The fever chart makes the same information visual. Plot percent of the critical chain complete against percent of buffer consumed. Points that drift above the proportional line move into yellow and then red. The chart is an early-warning system, not a post-mortem.

When the burn ratio is climbing, or the fever chart is in the red, the old patterns are no longer working. That is the moment to stop defending what used to succeed and start adjusting. The ratio does not care how many years of experience you have. It only reports whether the current strategy is protecting the date.

Simple tools overcome the bias. The buffer burn ratio does not require new software or an organizational redesign. It only requires that you compare the remaining work to the remaining protection and act on what the number says. When the ratio rises, the patterns that once worked no longer work. That is the moment when experience stops being an advantage and becomes the problem. How to cut project lead time without padding every task is in Projects in Less Time.