We have described how consensus allows a system to decide
which transactions enter the chain
and how a shared state is maintained over time.
That architecture brings clear benefits.
It also introduces constraints
that follow directly from the same design.
Understanding those constraints is necessary
to understand when blockchain systems
are suitable to use and when they are not.
1. Transaction and validation time
In a blockchain system, a transaction is not completed
when it is first submitted.
It must be propagated across the network, independently verified,
and included in a block that becomes part of the shared history.
This process exists because the system prioritizes
agreement and consistency across multiple participants,
not immediate execution.
Why this matters:
Delays are not a failure of the system.
They are the visible cost of distributed validation.
This explains why blockchain interactions
often feel slower than those in traditional systems.
2. Security depends on key control
Blockchain systems do not protect identities.
They protect cryptographic authority.
If a private key or seed phrase
is compromised, the system cannot distinguish
between legitimate and illegitimate use.
There is no native mechanism to block access
or reverse actions implicitly.
Why this matters:
Security shifts from institutions to key management.
Once control is lost, the system cannot intervene
unless a new transaction explicitly does so.
This significantly raises the cost of mistakes and misuse.
3. Transactions cannot be modified
Once a transaction is finalized,
it becomes part of the immutable record.
Past state is never edited.
Corrections are applied by adding new state on top of the existing one.
Why this matters:
Error correction is explicit, not discretionary.
This property follows directly from how validation and authority
are structured.
4. Applications are single-objective by nature
Blockchains are designed to enforce specific rules over shared state.
They are not general-purpose systems optimized for flexibility.
Applications tend to focus
on a narrow objective with clearly defined execution paths.
Why this matters:
Precision is favored over adaptability.
This limits what applications can do,
but strengthens what they are designed to guarantee.
5. Development is structurally complex
Building on blockchain systems requires understanding
cryptography, state management, and deterministic execution.
Errors are not easily corrected
once code is deployed.
Why this matters:
Development is slower and more demanding
than in traditional environments.
The cost of insufficient understanding is significantly higher.
6. No intermediaries, no safety net
Without intermediaries, there is no entity
that can pause, override, or arbitrate system behavior.
Responsibility is carried directly by the participant.
Why this matters:
The absence of mediation creates a sense of exposure.
Users interact directly with the system without implicit protection.
7. Friction emerges from unfamiliar models
Blockchain systems introduce concepts
that differ from established digital practices.
Key custody, finality, and irreversible actions
require different operational assumptions.
Why this matters:
Even when the system functions correctly,
interaction is more complex.
Adoption is affected by that complexity,
not by technical failure.
8. Regulation assumes intermediated systems
Most regulatory frameworks are built around custody,
central operators, and reversible control.
Decentralized systems
do not align cleanly with these assumptions.
Why this matters:
Regulatory integration is slow and uneven.
New legal structures are required
to accommodate this architecture.
Final reflection
Blockchain systems do not remove trade-offs.
They make them explicit.
Distributed validation introduces time.
Self-custody introduces responsibility.
These limitations are not accidental.
They emerge from the same foundation
that produces the system’s guarantees.
This is the eighth block.
We start from the first block.
And we build from there.
#blockchain