TOC course · Lesson 1 of 6
See the system before naming the constraint
Your first win is to stop calling every busy resource or large queue “the constraint.” Define the goal, boundary, and flow unit first.
The one idea
A value stream is an end-to-end, customer-triggered flow that produces a customer outcome—not an org chart or ticket workflow. A constraint exists only in relation to that system goal. “Engineers are busy” is an observation. “RFC clarification limits the rate at which approved work becomes invoiceable without harming SLA” is a constraint hypothesis: it names a system, a goal unit, a limiting mechanism, and a necessary condition.
Apply the frame to IT-Premium
| Element | Recurring services | RFC / projects |
|---|---|---|
| Flow unit and exit | An onboarded, reliably operated service that is retained and renewed—not merely a paid invoice. | A change approved, delivered, verified, invoiced, and commercially closed—not merely a closed ticket. |
| Cadence | Continuous operation plus monthly billing and renewal cycles. | Discrete work moving through discovery, approval, execution, and closure. |
| Immediate evidence gap | Абонплата reliably separates recurring income, but MRR still requires contract normalization and churn requires customer-status history. | 17 of 30 open RFCs sat in clarification; only 6 were executing. |
| Necessary condition | Protect SLA, retention, and recurring margin. | Do not advance commercially or technically unready work. |
They share engineers and cash collection, but combining them into one queue would erase different flow units and decision points. Incidents and service requests are a shared-capacity demand loop, not a third revenue value stream. TOC focuses a system; poor system boundaries produce poor focus.
Turn an observation into a hypothesis
Name the goal unit
For the RFC stream: more approved, delivered, invoiceable changes—not more tickets touched.
Name the limiting mechanism
Candidate: decisions and dependencies required to move work from clarification to an approved, scheduled plan.
Name the guardrail
Recurring-service SLA must not deteriorate while project flow improves.
Name the confirming pattern
If clarification is the constraint, twice-weekly decision clinics should increase ready-plan transitions and later invoiceable work without worsening SLA.
Practice: retrieve the distinctions
Your field exercise
Pick one real service workflow. Write five lines: boundary, goal, flow unit, necessary condition, and current constraint hypothesis. Then add one result that would prove your hypothesis wrong.
Primary reading
- Goldratt Research Labs, “What is Theory of Constraints?” — focus on system, goal, necessary conditions, measurements, and the constraint.
- IT-Premium Value Streams & Flow Constraints — reread the Level 0/1 mapping guidance, stream separation, and RFC phase distribution.