Data quality checklist and defect taxonomy templates

Why data quality fuels Customer Experience outcomes

Executives fund journeys, but data quality powers them. Clean, complete, and timely data drives accurate insights, efficient operations, and trustworthy automation across service channels. Poor data quality destroys outcomes by inflating rework, breaking personalisation, and eroding customer trust. Independent analyses estimate the annual economic impact of bad data in the trillions, which signals a structural risk, not a minor nuisance.¹ (hbr.org)

What is a practical data quality checklist?

Leaders need a simple, repeatable checklist that fits real processes. A data quality checklist is a compact control set that verifies whether critical data assets meet defined thresholds for fitness of use. The checklist aligns to canonical characteristics such as accuracy, completeness, consistency, credibility, and timeliness, enabling standardised assessment across datasets and journeys. A shared checklist reduces debate, shortens remediation cycles, and creates a measurable contract between data producers and data consumers. Global standards bodies describe these characteristics in detail and separate inherent data traits from system-dependent traits, which helps teams diagnose root causes faster.² (iso.org)

How should CX teams define “good enough” quality?

Teams should define “good enough” by context, not perfection. Contact centre routing needs high availability and freshness. Personalisation needs high accuracy and completeness at the customer-profile level. Regulatory reporting needs traceability and credibility. A robust model separates what belongs to the data itself from what the hosting system introduces, which clarifies the bar for each use case and prevents gold-plating. The ISO/IEC 25012 model provides a reference vocabulary that keeps discussions precise and avoids cross-team ambiguity when setting thresholds for accuracy, completeness, consistency, credibility, and timeliness.² (iso.org)

Where does lineage fit in a quality program?

Quality does not live in isolation. Data lineage documents how datasets move, transform, and join across pipelines, making it easier to spot where defects enter and how they propagate. Open standards for lineage events allow tools to interoperate, so observability and governance can share one narrative of the truth. A shared lineage model also accelerates incident response by revealing upstream jobs and downstream consumers, which shortens time to mitigate customer impact. OpenLineage provides an extensible specification and object model to emit and consume lineage events across the modern data stack.³ (openlineage.io)

What mechanism enforces the checklist at scale?

Validation enforces the checklist. Teams codify expectations as machine-checkable tests that run in pipelines and in orchestration. When a dataset violates a rule, the run fails, alerts fire, and data never silently degrades customer journeys. Leading open-source frameworks provide an expectation vocabulary, profiling, and living documentation. These frameworks turn quality from a sporadic audit into a continuous control. The expectation gallery concept, combined with auto-generated data docs, gives analysts and engineers a shared source of truth for tests, results, and lineage-aware context.⁴ (greatexpectations.io)

How does reference architecture simplify adoption?

Architecture clarifies responsibilities. A reference model defines the planes where quality controls operate: ingestion, storage, transformation, serving, and consumption. It also names cross-cutting fabrics such as security, governance, and lifecycle management so teams can place controls consistently. Public bodies publish neutral reference architectures for big data that teams adapt to their scale and risk profile. These references help avoid tool-first decisions and keep the focus on outcomes across the data lifecycle.⁵ (nvlpubs.nist.gov)

Data quality checklist template you can copy today

Use this checklist to standardise controls across customer, product, and interaction datasets. Keep it short. Keep it in version control. Review it in change advisory boards and quarterly business reviews.

DATA QUALITY CHECKLIST v1.0

Scope
- Dataset name:
- Owner (product + technical):
- Purpose and critical use cases:

Controls
1) Accuracy
   - Define source of truth fields (e.g., email, phone).
   - Set permitted values and reference lists.
   - Validate with expectation tests on ranges, regex, and cross-field logic.

2) Completeness
   - Define mandatory fields by use case.
   - Set null thresholds by field and record segment.
   - Fail pipeline if thresholds breached; quarantine and alert.

3) Consistency
   - Align formats, units, and encodings to standards.
   - Enforce schema contracts and backward compatibility rules.
   - Validate cross-system keys and join cardinality.

4) Credibility
   - Record data provenance and certification status.
   - Require stewardship approval for sensitive fields.
   - Track validation history in data docs.

5) Timeliness
   - Define freshness SLOs per consumer.
   - Monitor late-arriving data and ingestion delays.
   - Escalate if SLOs breached; trigger rollback or degrade gracefully.

6) Lineage & Traceability
   - Emit lineage events for jobs and datasets.
   - Link transformations to code commits and tickets.
   - Provide impact analysis before schema changes.

7) Monitoring & Alerts
   - Route failures to on-call with run metadata.
   - Publish dashboards for stakeholders.
   - Retain validation artifacts for audits.

8) Exception Management
   - Document risk acceptance and expiry dates.
   - Track hotfixes and backfills with outcomes.
   - Review exceptions in QBRs.

Sign-off
- Data Owner:
- Steward:
- Consumer Representative:
- Date:

The checklist aligns with recognised quality characteristics and turns them into run-time controls and accountability rituals.²⁴⁵ (iso.org)

Defect taxonomy template that speeds root cause analysis

A defect taxonomy gives teams a shared language to classify and prioritise incidents. This structure reduces time to triage, improves trending analysis, and clarifies where to invest fixes. Use the taxonomy below to tag incidents at detection, then refine during post-incident review.

DEFECT TAXONOMY v1.0

Category → Subcategory → Example → Typical Root Cause → Primary Control

1) Accuracy
   - Invalid values → negative age → missing domain constraints → expectation test
   - Reference mismatch → country code not in ISO list → stale reference data → lookup validation

2) Completeness
   - Missing mandatory → email null on active customers → upstream filter bug → null threshold check
   - Truncated records → partial loads → connector timeout → load reconciliation

3) Consistency
   - Schema drift → unexpected column type → uncoordinated release → contract test
   - Duplicate keys → multiple customer_ids → dedupe failure → uniqueness test

4) Credibility
   - Unverified source → shadow spreadsheet upload → bypassed governance → provenance policy
   - Certification expired → stale approval → process lapse → stewardship workflow

5) Timeliness
   - Late batches → SLA breach → upstream job delay → freshness SLO monitor
   - Out-of-order events → mis-sequenced clicks → clock skew → event-time watermarking

6) Lineage & Traceability
   - Unknown origin → dataset with no upstream → missing emission → lineage spec enforcement
   - Broken link → job renamed → inconsistent tags → CI check on lineage continuity

7) Security & Compliance
   - PII leak → unmasked phone in analytics mart → masking gap → field-level policy
   - Policy violation → data retained past TTL → lifecycle oversight → retention control

This taxonomy mirrors quality dimensions and ties each defect class to a primary preventive control, which accelerates learning loops and investment decisions.²³ (iso.org)

How to measure impact and prove value

Leaders should measure both prevention and business impact. Prevention metrics include test coverage, validation pass rates, schema change lead time, and lineage completeness. Business impact metrics include deflection of incident hours, reduction in refunds due to misrouting, and improvement in first contact resolution. Tie improvements to specific controls to show attribution. Prominent studies argue that the cost of poor data quality is not marginal, which strengthens the case for sustained investment and governance.¹ (hbr.org)

What are the next steps for an enterprise rollout?

Start small, then scale deliberately. Pick one critical journey, such as complaint handling or proactive outage messaging. Implement the checklist, the taxonomy, and at least ten expectations that cover the five key characteristics. Generate profiling reports to find blind spots and calibrate thresholds. Instrument lineage for the pipeline to enable change impact analysis. Publish data docs so consumers can see quality trends and remediation history. Open-source tools provide strong starting points for profiling, testing, and documentation, which lowers entry cost and raises transparency.⁴⁶ (docs.greatexpectations.io)

Evidentiary layer and definitions

This unit uses the following anchor definitions to stabilise quality conversations. Accuracy means values correctly represent reality. Completeness means all required values exist for a given use. Consistency means values agree across systems and conform to contracts. Credibility means data provenance and certification status are trustworthy. Timeliness means data arrives and is processed within required windows. These definitions align with international standards and are broadly adopted in enterprise governance.²⁵ (iso.org)


FAQ

What is the fastest way to adopt the Customer Science data quality checklist in a contact centre environment?
Start with one journey and one dataset, such as interaction routing. Implement the eight checklist sections, create ten expectations for accuracy, completeness, consistency, credibility, and timeliness, and publish data docs so supervisors can see validation history and trends. Use lineage to assess change impact before release.⁴⁵ (docs.greatexpectations.io)

How does OpenLineage improve Customer Science governance and incident response?
OpenLineage standardises lineage events across tools. Emitting run, job, and dataset events enables rapid upstream and downstream impact analysis, which reduces time to mitigation when a defect appears in a CX dataset.³ (openlineage.io)

Which data quality characteristics matter most for personalisation at scale?
Accuracy and completeness of customer attributes drive relevance, while timeliness controls ensure fresh context. Consistency across channels prevents contradictory messages. Credibility provides the assurance that sources and approvals are reliable for regulated use.² (iso.org)

Why should executives care about the economic cost of bad data in service transformation?
The macro cost of poor data quality is measured in the trillions annually, which highlights the strategic scale of the issue. This cost manifests locally as rework, lost sales, regulatory exposure, and degraded customer satisfaction.¹ (hbr.org)

How do Great Expectations and data docs help Customer Science stakeholders?
Great Expectations turns quality rules into code and produces human-readable data docs. These artifacts make tests, results, and profiling visible to analysts, engineers, and leaders, creating a shared source of truth and audit trail.⁴ (docs.greatexpectations.io)

Who owns the checklist and defect taxonomy inside an enterprise?
Data owners and stewards jointly own the documents. Product managers for key journeys approve thresholds, and engineering teams codify expectations in pipelines. Lineage owners ensure traceability is complete for impact assessment.²³ (iso.org)

Which profiling tools accelerate threshold setting for Customer Science implementations?
Profiling libraries such as ydata-profiling generate automated reports with distributions, missingness, and correlations. These insights help calibrate initial thresholds and identify outliers before tests go live.⁶ (ydata-profiling.ydata.ai)


Sources

  1. Bad Data Costs the U.S. $3 Trillion Per Year — Thomas C. Redman, 2016, Harvard Business Review. https://hbr.org/2016/09/bad-data-costs-the-u-s-3-trillion-per-year

  2. ISO/IEC 25012:2008 — Data Quality Model — ISO/IEC JTC 1/SC 7, 2008, ISO. https://www.iso.org/standard/35736.html

  3. About OpenLineage — OpenLineage Project, 2025, OpenLineage.io. https://openlineage.io/docs/

  4. GX Expectations Gallery and Data Docs — Great Expectations, 2025, GreatExpectations.io. https://greatexpectations.io/expectations/ and https://docs.greatexpectations.io/docs/0.18/reference/learn/terms/data_docs/

  5. NIST Big Data Interoperability Framework, Volume 6: Reference Architecture — NBD-PWG, 2015–2019, NIST Special Publication 1500-6. https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.1500-6r2.pdf

  6. YData Profiling Documentation — YData, 2025, ydata-profiling. https://ydata-profiling.ydata.ai/

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