Block's Prototype Rule Puts Product Proof Ahead of Slide Decks

Jack Dorsey's prototype-first meeting rule at Block is a direct challenge to the culture of polished slide decks. On Sequoia's Long Strange Trip podcast, Dorsey said Block employees had moved from bringing presentations or Google Docs to meetings to bringing prototypes built on real or simulated data. The shift changes what gets tested in the room.

A deck can describe a product elegantly. A prototype forces the team to show whether the idea has shape. It may be a rough model, a workflow, a sketch, a data simulation or a functional tool, but it gives the discussion an object. A working object makes assumptions easier to challenge than a sequence of confident slides.

Prototypes expose friction earlier

The main advantage of a prototype is that it reveals where a story breaks. A payment flow that sounds clean in a meeting may fail when a user has an edge case. A data product may look convincing until the team has to show which data exists, which is simulated and which dependency is missing.

Early friction is valuable while the cost of change is still low. Teams can adjust the path, discard an approach or test a narrower version before the organization commits more time. The meeting becomes less about persuasion and more about contact with the actual work.

Slides still have a legitimate job

The move away from slide decks should not be read as a ban on thinking. Slides and documents can still summarize strategy, legal constraints, market context and tradeoffs. The problem appears when the deck becomes a substitute for product evidence.

Block's rule is stronger if it treats prototypes and written context as complements. A prototype can show how a thing behaves. A memo can explain why the thing should exist, which constraints matter and what the team still does not know. Product culture weakens when either one pretends to do both jobs.

AI lowers the cost of showing work

Dorsey's argument fits the broader AI moment because AI tools can make rough prototypes faster to build. Teams can turn a concept into a clickable model, a data-backed demo or a small internal tool without waiting for a full development cycle.

Faster prototyping changes leadership expectations. If a rough version can be produced quickly, executives may ask for evidence earlier. The benefit is faster learning. The danger is mistaking a fast demo for a production-ready system, especially in fintech, where compliance, fraud controls, reliability and audit trails matter.

Fintech prototypes need extra restraint

Block operates in payments and financial services, so the prototype rule has to respect regulated reality. A model can show a customer flow or data idea, but it cannot prove that the system is secure, compliant, scalable or ready for live money movement.

The distinction between a demo and a live system is not bureaucracy. It protects the company from falling in love with the demo. In financial products, the difficult work often sits behind the screen: identity checks, dispute handling, ledger accuracy, risk review, customer support and operational resilience.

The rule also changes status inside the company

Meeting cultures reward different people depending on what they ask teams to bring. A slide-heavy culture often favors the person who can frame, narrate and defend an idea. A prototype-heavy culture favors the person who can make the idea tangible before the room loses patience.

A prototype-heavy culture can be healthy if it rewards builders and reduces presentation theater. It can become unhealthy if every strategic question is rushed into a demo before the problem is understood. The stronger form of the rule asks for proof without treating speed as the only proof.

Execution should not become another ritual

Block has to use prototypes to learn instead of performing a new management fashion. If teams bring models that expose tradeoffs, the meetings can become more honest. If teams bring polished mockups designed only to impress, the company has replaced one theater with another.

Dorsey's rule is strong because it shifts attention from explanation to evidence. Its limit comes from the stages of evidence. A prototype can start a better conversation, but it does not end the conversation. Product proof still has to survive users, systems, compliance and time.