Pattern · Foundational
Exception Creep
A simple process accumulates special cases and workarounds until nobody understands the whole system.
Brilliant QuestPublished 9 October 2026Updated 2026-10-09
Illustrative structure
Standard path
Exceptions branch
Hidden rules
Common indicators include…
- The documented process rarely covers a real case
- Spreadsheets contain unexplained conditional rules
- Exceptions repeatedly become permanent workarounds
- Changes break cases nobody remembered
Why it may happen
Local fixes solve immediate problems but are not reviewed together. Legitimate business variation and accidental complexity become entangled.
What it can cost
Change becomes harder to predict and testing becomes incomplete. Automating the current path without understanding its branches can encode complexity rather than remove it.
Questions worth asking
- Which exceptions are legitimate requirements and which are historical fixes?
- Who can retire a rule, and what evidence would justify that?
- How often does each branch occur, and what happens when it fails?
Possible interventions
- Collect concrete exception cases with owners and reasons.
- Remove obsolete branches and simplify before automating.
- Represent remaining rules explicitly and test boundary cases.
Verification required
This is an explanatory pattern, not a finding about your organisation. Establish whether it is present through a real example, records and the people involved; retain contradictory evidence.