Why the Variance Is Almost Never the Schedule
Six causes sit ahead of the schedule, and checking them in order takes ten minutes. Most operations start at the end.
Labour is over budget and the schedule gets blamed. In practice the schedule is rarely the cause, and the real one is usually two questions away.
The planning problem in “Why the Variance Is Almost Never the Schedule” becomes clearer when scheduled hours can be compared with actual project and time records. Teams researching more information for employee monitoring for performance reviews can add that operational evidence, while demand, service levels and manager judgement remain necessary to explain why a variance occurred.
The order to check
One: did demand differ from forecast?
For an independent reference related to “Why the Variance Is Almost Never the Schedule”, consult the CIPD workforce-planning resources; it provides a useful external check on scheduling, working-time and workforce-planning assumptions.
Two: was the mix different — more complex work, different customers?
Three: was there absence, and how was it covered?
Four: was there overtime or agency, and why?
Five: did anything operational change — a system, a process, a new starter cohort?
Six: was the schedule itself loose?
Six is last because it is least often the answer.
Why demand comes first
A busy week over budget is a success reported as a failure.
Checking demand takes one minute and reframes the whole conversation.
An operation that does not record forecast demand cannot do this, which is the practical argument for recording it.
The mix cause
Same number of customers, harder ones.
Same volume, different product.
More new staff, so everything took longer.
This cause is real, common, and almost never checked because it requires knowing the normal mix.
The cover cause
Absence covered at overtime or agency produces cost variance with no hours variance.
Which looks like a rate problem and is an absence problem.
Separating it points at the absence plan rather than at the schedule, and those are different fixes.
The change cause
A new system that is slower until people learn it.
A process change that added a step.
A cohort of new starters.
Each produces a temporary cost increase that is entirely explainable and entirely invisible unless somebody names it.
Why the schedule gets blamed anyway
It is the thing the manager controls, so it is the thing that gets questioned.
And it is the only cause with an obvious remedy.
Which means the available answer is applied to whatever the cause was, and the actual cause persists.
The ten-minute discipline
Before explaining an adverse variance, work the six in order.
Write one line for each.
The explanation that comes out is specific and checkable, and it points at a fix that will work.
"The schedule was tight" points at nothing.
What this does upward
A manager who reliably identifies the real cause is trusted with the next conversation.
One who always says the schedule will be told to cut it.
Which is the practical reason to do the ten minutes.
What to check
When your variance was last adverse, which of the six was it?
Can you check demand against forecast?
Do you know your normal mix?
And does anybody write down the cause, or just the number?