There are two key and critical things that are needed to measure our predictability in a probabilistic way — the probability of us meeting our promises (i.e. not in a deterministic way).
Our predictability is very important to our customers who are waiting for their “valuable things” to be delivered by us.
These two key and critical things are:
1) the ratio of Actual versus Planned — which is also known as Achievement Ratio (AR).
To be predictable, the AR must consistently be between 0.80 and 1.00 (in percentage, which is 80% and 100%). Otherwise, your process or system is unpredictable.
Formula: AR = Actual / Planned.
This formula applies to everything! For example:
- Sprint (Iteration) AR = Actual Velocity / Planned Velocity.
- Team Program Increment AR = Sum of all (Committed and Uncommitted) PI Objectives’ assessed scores / Sum of all Committed-Only PI Objectives’ assigned scores
- Program Predictability Measure is the average of Teams’ Program Increment AR
- Your predictability = What promises you kept / what you have promised.
- Example: On the twelfth day of Christmas you promised 12 Golden Rings and you only delivered 6 Golden Rings… your predictability = 6 / 12 = 0.5 = 50% ! Not good.
2) the trend of AR over a period.
If the AR is between 80% and 100% … and it is consistently within that range for over a certain period, then the process is “in control”; otherwise, the process is “out-of-control”… there is variability present in the process that is causing the process to potentially be unpredictable — it must be investigated sooner rather than later.
Flow Interruptions occur. Could be because of bottlenecks, delays, etc. Interruptions cause wastes. Learn to see these wastes… and then remove these… to increase Flow Predictability.
Related Blog Post: I Trust My Train! It is Very Predictable!