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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…

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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.
🧪 Example

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).

⚠️ Pitfall

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).

⚠️ Pitfall

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.

💡 Expert tip

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.

🤖 AI

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#

✻ Written by Claude Sonnet 5.5