Bitcoin Custody Completeness Check

Verifying All Custody Components Are Present

This memo is published by CustodyStress, an independent Bitcoin custody stress test that produces reference documents for individuals, families, and professionals.

What Completeness Would Mean

A bitcoin custody completeness check asks whether a custody arrangement has everything it needs. Nothing missing. No gaps. All components present. All connections made. The appeal of completeness is that it suggests a boundary—once everything necessary is in place, the arrangement is done. But completeness faces a fundamental obstacle: the person checking cannot see what they do not know to look for.

This assessment considers how completeness checking fails when applied by the same person who created the arrangement. Blind spots, assumptions, and unknown unknowns limit what self-assessment can reveal.

---

What Completeness Would Mean

A complete custody arrangement would have every component necessary for successful access by the intended parties under all relevant circumstances. Every piece of information documented. Every dependency addressed. Every scenario covered. Nothing left out that could cause failure.

Completeness implies a finite set of requirements. If requirements can be listed, they can be checked. If all items on the list are satisfied, the arrangement is complete. This makes completeness seem achievable through thoroughness—create a comprehensive list and work through it.

But the requirements for successful custody access are not finite in a knowable way. They depend on future circumstances that cannot be fully anticipated. They depend on other people's capabilities and behaviors that cannot be fully known. They involve technical and legal environments that will change. The set of things that might matter is open-ended.

Completeness also assumes requirements are visible. If something is missing, it can be noticed. But invisible requirements—things the holder does not know they need—cannot be checked by definition. The holder cannot verify the presence of something they do not know to look for.

---

The Blind Spot Problem

Every person has blind spots—areas where they do not see what is there or see what is not there. Blind spots are invisible to the person who has them. This is their defining feature. A holder checking their own custody arrangement cannot see their own blind spots.

Knowledge creates blind spots. The holder knows their passphrase, so they may not recognize that it is undocumented. They know where their hardware wallet is stored, so they may not recognize that the location is not recorded anywhere. Their knowledge fills gaps that will be empty gaps after they are gone.

Familiarity creates blind spots. The holder has used their custody system many times. They navigate it automatically. Steps that are intuitive to them may be confusing to someone encountering the system for the first time. The holder cannot easily assess what the system looks like to someone unfamiliar with it.

Assumptions create blind spots. The holder assumes their spouse knows certain things. They assume their heir can figure out certain steps. They assume certain technology will continue to exist. Each assumption may be wrong, but the assumption itself prevents the holder from seeing the gap.

---

The Self-Assessment Trap

The most common completeness check is self-assessment. The holder reviews their own arrangement and asks themselves what is missing. This is convenient but structurally flawed. The reviewer and the creator share the same blind spots, assumptions, and knowledge gaps.

Self-assessment tends to confirm completeness rather than challenge it. The holder created the arrangement believing it was sufficient. Reviewing it, they see what they expected to see. The same perspective that shaped creation shapes assessment. Problems that were invisible during creation remain invisible during review.

Motivation affects self-assessment. Finding problems requires admitting imperfection. It creates work. It challenges the sense that the task is done. The holder may unconsciously avoid looking too hard at areas where problems might lurk. They may interpret ambiguity favorably rather than cautiously.

Self-assessment lacks the friction of external review. A different person brings different knowledge, different assumptions, and different perspective. They ask questions the holder would not ask. They get confused where the holder sees clarity. This friction reveals problems. Self-assessment lacks this friction by definition.

---

Documentation as Incomplete Capture

Completeness checking often focuses on documentation—are all the instructions written down, all the locations recorded, all the procedures explained? But documentation captures only what the documenter thinks to include. It cannot capture what the documenter does not recognize as needing capture.

The holder writes documentation from their own perspective. They explain what seems non-obvious to them. What seems obvious remains unexplained because explaining it feels unnecessary. But what is obvious to the holder may not be obvious to the heir. The documentation is complete from the holder's perspective but incomplete from the heir's perspective.

Procedural knowledge is particularly hard to document completely. The holder knows how to do things they have done many times. Translating tacit knowledge into explicit instructions loses details that seemed unimportant but turn out to matter. The documentation captures the procedure as the holder consciously thinks about it, not as they actually perform it.

Documentation completeness checking by the holder suffers from the same blind spot problem as other self-assessment. The holder reads their documentation and understands it. Of course they understand it—they wrote it. Whether someone else would understand it requires a different reader, not the same reader checking their own work.

---

Unknown Unknowns

Known gaps can be addressed. The holder notices they have not documented a password and documents it. Known unknowns can be flagged. The holder knows they do not know whether their heir understands bitcoin and can investigate. Unknown unknowns cannot be addressed because the holder does not know they exist.

Unknown unknowns are not rare edge cases. They are common features of complex arrangements. The holder may not know what software their heir has access to. They may not know what skills their heir lacks. They may not know what conflicts might emerge among heirs. These unknowns are not exotic—they are ordinary aspects of inheritance planning that escape attention.

Completeness checking cannot reveal unknown unknowns to the person who does not know them. External perspectives can sometimes surface unknown unknowns—another person may ask "what about X?" where X never occurred to the holder. But the holder alone cannot systematically identify what they do not know they do not know.

The passage of time creates new unknown unknowns. Technology changes in ways the holder could not anticipate. Family situations evolve unexpectedly. Legal environments shift. The arrangement that was complete given known circumstances becomes incomplete when unknown circumstances emerge.

---

Checklists and Their Limits

Checklists are tools for completeness checking. They list items that might be needed. The user checks each item. Anything not checked is identified as potentially missing. Checklists impose structure on completeness assessment.

But checklists can only contain items someone thought to include. They reflect the knowledge and assumptions of whoever created them. A checklist created by the holder reflects the holder's blind spots. A checklist created by someone else reflects that person's assumptions about what matters, which may not match the holder's specific situation.

Generic checklists miss situation-specific requirements. Every custody arrangement is unique. Generic checklists cover common elements but cannot anticipate every element that matters for a specific holder. Completing a generic checklist may miss custom elements that are essential for this particular arrangement.

Checklists create a false sense of completeness. If all items are checked, the task feels done. But the items on the checklist may not be the items that actually matter. A checked checklist provides comfort that may not be warranted. The completeness it suggests is completeness relative to the checklist, not completeness relative to actual requirements.

---

External Review Limitations

External review—having someone else check the arrangement—can surface some issues self-assessment misses. A different perspective brings different blind spots, which may not overlap with the holder's blind spots. Where the holder cannot see, the reviewer might.

But external reviewers have their own limitations. They may not understand the holder's specific situation. They may bring assumptions from their own experience that do not apply. They may miss things unique to this arrangement that a holder-specific blind spot would also miss.

Reviewers can only check what they are given access to. If the holder does not share certain information for security reasons, the reviewer cannot assess its completeness. The review is limited to the subset of the arrangement the holder reveals, which may not be the subset where problems lurk.

Professional reviewers may know about custody arrangements generally but not about this holder specifically. They may declare an arrangement complete based on general standards while missing holder-specific gaps. Their expertise provides confidence that may not account for the arrangement's particular context.

---

Completeness as Process Rather Than State

Seeking a complete arrangement as a static state may be the wrong framing. Arrangements exist in time. Requirements change. Components degrade. What is complete today may be incomplete tomorrow through no deliberate change.

Completeness might be better understood as ongoing attention rather than achieved status. Regular review. Periodic updating. Continued communication with heirs. This process never arrives at final completeness but maintains the arrangement in reasonable condition over time.

Treating completeness as a state creates risk. The holder believes the arrangement is complete and stops paying attention. Degradation occurs unnoticed. Years later, the supposedly complete arrangement has gaps that developed since the last check. The label of completeness prevented the ongoing attention that would have revealed emerging problems.

Accepting incompleteness may be more realistic and more useful. Every arrangement has gaps—some known, some unknown. Rather than seeking to eliminate all gaps, the holder can work to reduce major gaps while accepting that minor gaps and unknown gaps will persist. This framing sets expectations that match reality.

---

Conclusion

A bitcoin custody completeness check faces the fundamental problem that the checker cannot see their own blind spots. Knowledge, familiarity, and assumptions create invisible gaps that self-assessment cannot reveal. The same perspective that shaped the arrangement shapes its review.

Documentation captures only what the documenter thinks to include, missing what seems obvious to them but may not be obvious to heirs. Unknown unknowns exist in every complex arrangement and cannot be identified by the person who does not know they exist. Checklists provide structure but only cover what their creators anticipated.

Completeness as a final state may be an unrealistic goal. Arrangements change over time. Requirements evolve. External reviews help but have their own limitations. What may be achievable is ongoing attention that maintains reasonable condition while accepting that true completeness remains unverifiable.

---

System Context

Examining Bitcoin Custody Under Stress

Bitcoin Cognitive Decline

Is My Bitcoin Custody Credible

← Return to CustodyStress