

- Description
- Ancienne caisse enregistreuse mécanique en laiton et acajou : compter ce que coûte et ce que rapporte
- Source
- Alf van Beem · original page
- Licence
- CC0 Public domain
Cost and Value Steering (Data FinOps)
Modern data platforms charge based on usage: compute capacity, storage, queries, per-user licenses. A data product can therefore see its cost grow without…
Level: 🟢→🔴 · Theme code: FIN
Why this theme#
Modern data platforms charge based on usage: compute capacity, storage, queries, per-user licenses. A data product can therefore see its cost increase without anyone deciding anything: a model that gets bigger, a refresh changed from daily to hourly, a poorly written query on shared capacity. Conversely, poorly targeted savings can degrade service. FinOps (a discipline popularized by the FinOps Foundation) brings three ideas: make cost visible, assign it to who causes it, then optimize it in relation to value. This theme covers the financial management of the data product; detailed Power BI license and capacity costs are covered in BI matrix — Cost, Licensing, and Capacity, and expected value in VAL. Offers and pricing change quickly: always verify with the vendor (status 2026-10, not detailed here).
What this theme measures#
- Axis: from cost ignorance to continuous value/cost trade-offs.
- Key indicator: share of total cost assigned to a data product and an owner, and unit cost (per active user, per query, per refreshed TB).
- Unit: % of assigned cost; cost per active user per month; budget/actual variance; value/cost ratio per product.
The five levels#
| Level | Short name | Promise | Typical indicator (orders of magnitude) |
|---|---|---|---|
| 1 | Opaque | The bill arrives; no one knows what makes it up or why it varies. | 0% of cost assigned |
| 2 | Visible | Total cost is known and tracked by category (storage, compute, licenses, people). | Monthly cost by major category |
| 3 | Assigned | Each data product has a known cost and an owner accountable for it. | ≥ 80% of cost assigned to a product |
| 4 | Steered | Budgets, alerts, and optimizations are tracked; unit cost is compared to value; drifts are handled quickly. | Budget variance < 10%; alert before overrun |
| 5 | Arbitrated | Every dollar is arbitrated based on value: optimize, invest, or stop, continuously. | Quarterly value/cost review; low-value products retired |
Milestones by level#
| ID | Milestone | Verifiable evidence |
|---|---|---|
| PD-FIN-1.1 | The cost categories of a data project are listed (people, infrastructure, licenses, support). | Dated category list. |
| PD-FIN-1.2 | The platform bill is accessible to the team. | Access to the billing tool or to a monthly export. |
| PD-FIN-1.3 | An annual budget exists, even a rough one. | Budget document. |
| PD-FIN-1.4 | A data budget owner is designated. | Name in the organization. |
| PD-FIN-2.1 | Monthly cost by major category is tracked over time. | Monthly table over ≥ 6 months. |
| PD-FIN-2.2 | Significant variations (> 20%) are explained. | Explanatory note for each variation. |
| PD-FIN-2.3 | Unused resources (forgotten environments, obsolete tables) are identified. | Inventory with a decision per line. |
| PD-FIN-2.4 | People costs (development and maintenance time) are estimated by product. | Workload estimate by product. |
| PD-FIN-3.1 | The cost of each data product (compute, storage, licenses, time) is calculated. | Cost table by product; written allocation method. |
| PD-FIN-3.2 | A cost owner is designated per product and knows their level. | Interview with three owners. |
| PD-FIN-3.3 | A unit cost is defined (per active user, per refresh, per TB). | Indicator calculated and published. |
| PD-FIN-3.4 | Refresh and heavy-query costs are assigned to their authors or products. | Measurement of compute chargeback. |
| PD-FIN-4.1 | Budgets per product and overrun alerts are configured. | Alert triggered and handled on a real case. |
| PD-FIN-4.2 | A regular optimization cycle (monthly or quarterly review) produces measured savings. | Report with quantified gains. |
| PD-FIN-4.3 | Performance/cost trade-offs are documented (refresh frequency, aggregates, partitioning). | Recorded decisions with before/after measurement. |
| PD-FIN-4.4 | The value/cost ratio is calculated for key products (VAL). | Value/cost table validated by a business third party. |
| PD-FIN-5.1 | The portfolio is arbitrated based on value and cost: invest, maintain, optimize, stop. | Product decisions over the last two quarters. |
| PD-FIN-5.2 | Low-value products are retired and the savings confirmed. | Retirement log and realized savings. |
| PD-FIN-5.3 | 12-month cost forecasting is based on usage and data volume growth. | Forecast compared to actual each quarter. |
| PD-FIN-5.4 | Optimization is integrated into development (cost estimated at design, checked in review). | “Cost” section in design reviews. |
Detailed reading by level#
🟢 Level 1 — Opaque#
- Signs: “IT pays for it”; a bill increase is discovered at closing.
- Gain: no monitoring effort.
- Does not guarantee: staying within budget; you can't arbitrate what you can't see.
- Difficulty: 1/5 · Effort: 1/5.
🟢 Level 2 — Visible#
- Signs: a monthly table; variations are explained; forgotten resources are listed.
- Gain: the first savings often come from a forgotten environment.
- Does not guarantee: assignment or linkage to value.
- Difficulty: 2/5 · Effort: 2/5.
🟡 Level 3 — Assigned#
- Signs: a cost per product; an owner per product; a unit cost; heavy refreshes are assigned.
- Gain: the discussion shifts from “it's too expensive” to “this product costs X for Y users.”
- Does not guarantee: that cost is optimized (it is only understood).
- Difficulty: 3/5 · Effort: 3/5.
A semantic model refreshed every hour for 40 users, of whom 6 are active. Assigned cost: 3 days of compute equivalent per month on shared capacity. At level 3, the owner sees the number; at level 4, frequency is changed to daily after verifying usage does not require it (about 90% savings on this model's compute, order of magnitude); at level 5, the product is compared to its value and merged with another.
🟡 Level 4 — Steered#
- Signs: budgets and alerts; monthly optimization review; recorded performance trade-offs; value/cost ratio calculated.
- Gain: predictable spending; recurring savings without degrading service.
- Does not guarantee: proper allocation: you can optimize very well a product that is no longer used.
- Difficulty: 4/5 · Effort: 4/5.
🔴 Level 5 — Arbitrated#
- Signs: quarterly value/cost review; confirmed retirements; reliable forecast; cost appears in every design review.
- Gain: every platform dollar is justifiable.
- Does not guarantee: value accuracy, always debatable (see VAL).
- Difficulty: 5/5 · Effort: 4/5.
Partial achievement and rating#
Assess on the portfolio of the five most expensive products: a milestone is worth 1 if all satisfy it, 0.5 if most do, 0 otherwise. Savings milestones require a before/after measurement, not an estimate.
A “partial 5”: a quarterly arbitration led to two retirements (5.1 and 5.2 at 1), the 12-month forecast is done but differs from actual by 25% (5.3 at 0.5), cost is not yet a design review criterion (5.4 at 0).
Saving at the expense of service: reducing the frequency of a refresh that a daily decision depends on. Symptom: savings observed, complaints. Remedy: every optimization consults the product owner and checks the SLA (EXP).
Arbitrary assignment: splitting shared cost pro rata by number of users penalizes small useful products. Remedy: write the allocation rule and review it annually; a simple stable rule is better than illusory precision.
The best indicator of a product to retire is cost per active user: a product with 40 registered users and 3 active users actually costs thirteen times more per head than its display suggests.
Moving to the next level#
Possible means (optional)
| Transition | Possible levers |
|---|---|
| 1 → 2 | Export the bill every month; list resources; appoint an owner. |
| 2 → 3 | Tag resources by product; choose an allocation rule; calculate unit cost. |
| 3 → 4 | Platform budgets and alerts; monthly review; cost dashboard by product (Project Metrics and Reporting). |
| 4 → 5 | Quarterly value/cost committee; expiration rule; cost criterion in design review. |
Cross-cutting pitfalls: (1) False positive — 100% assigned cost but through an arbitrary rule. (2) Goodhart — minimizing cost pushes removal of test environments or controls (QUA). (3) Hidden cost — human cost (support, fixes) often exceeds platform cost; do not omit it.
It summarizes a bill, spots cost anomalies, suggests query optimizations. It does not know business value and can recommend a saving that degrades a critical service; it also consumes capacity itself (tokens, compute): its cost belongs in the table, and its production uses must be budgeted.
See also#
- Same matrix: 01 Value · 06 DataOps · 10 Operations · 05 Modeling · README
- Other matrices: PI — Budget, Value, and Benefits (VAL) · DL — Performance and Scalability · BI — Cost, Licensing, and Capacity · BI — Performance and Data Volume
- Practice: Comparison — OneLake/Fabric vs Managed SQL Server for Power BI Reporting · OneLake + SaaS Mobile Apps: Architecture · SQL Server in SaaS — Architecture · Methods Specific to Data Projects
- Glossary · Rating: How to Read Scores, Ratings, and Legend
✻ Written by Claude Sonnet 5.5