Common Mistakes When Building an MVP and How to Avoid Them
The scope, validation, and execution mistakes that delay learning when launching a new digital product.
Erlan Carreira
Software Engineer & Entrepreneur
The most costly mistakes of an MVP are usually not isolated bugs. They are decisions that hinder learning: a broad audience, vague hypotheses, scope without criteria, launch without measurement, and an operation unable to support early users. Avoiding them requires defining beforehand what will be proven and how the team will react to the results.
Direct answer: the seven main mistakes
- trying to validate multiple hypotheses at the same time;
- choosing features by voting;
- confusing prototype with operational product;
- postponing security, support, and data;
- measuring sign-ups instead of value and repeatability;
- validating only at the end;
- continuing to invest without decision criteria.
Mistake 1: broad audience and problem
"Companies that need to improve processes" is not a testable segment. The context changes between sectors, sizes, and responsible parties. Choose a recurring situation, a user, and an initial buyer. This focus reduces channels, integrations, and exceptions, allowing for the observation of patterns.
Mistake 2: backlog as a sum of opinions
Requests from users, partners, and competitors do not carry the same weight. Relate each item to a hypothesis, risk, or obligation. If a feature does not change the ability to test, protect, or operate the journey, it can probably wait.
| Symptom | Consequence | Correction |
|---|---|---|
| Many personas | Incompatible flows | Choose an initial segment |
| Long delivery without use | Late feedback | Demonstrate complete journeys per cycle |
| Generic metrics | Decision by opinion | Define activation and repeatability |
| Improvised support | Loss of trust | Channel, responsible party, and logs before the pilot |
| Always growing scope | Cost without learning | Backlog separate from MVP criteria |
Mistake 3: treating prototype as production
Prototypes simulate interaction; they do not prove data integrity, authorization, concurrency, or recovery. If real users will depend on the system, handle error states, backup, access, and support according to the impact. The MVP can be small, but it should not mislead about its reliability.
Mistake 4: premature or disposable architecture
Microservices, queues, and high availability before knowing the load can slow down testing. On the other hand, ignoring migrations, observability, and permissions creates a foundation that is impossible to operate. Prefer a simple, modular, and measurable architecture, with reversible decisions and known limits.
Mistake 5: launching without instrumentation
Sign-ups and pageviews do not indicate if value has occurred. Define journey events, time to activation, return, error, and abandonment. Google's HEART framework helps connect happiness, engagement, adoption, retention, and task success, but each product needs its own definitions.
Mistake 6: validating at the end
Show executable increments frequently. Acceptance criteria should include rules, permissions, states, and example data. Users and business owners need to participate before decisions accumulate.
Mistake 7: not defining when to stop
Before the pilot, record limits: how many people will be invited, for how long, what behavior is expected, and what result will change the course. A well-interpreted negative result saves capital. Prolonging a test indefinitely without criteria only turns uncertainty into cost.
Preventive checklist
- Hypothesis and segment written in one sentence.
- Success and closure criteria defined before construction.
- One main journey prioritized.
- Frequent demonstrations with realistic data.
- Backlog separate from validation scope.
- Activation, repeatability, and error events.
- Minimum security, backup, logs, and support.
- Product owner available for decisions.
- Assumptions and risks reviewed each cycle.
- Decision meeting scheduled after the pilot.
Primary sources
See essential features of a SaaS MVP and how we organize the development of MVP.
Erlan Carreira
Software Engineer & Entrepreneur
Specialist in software development, automation, and SaaS. I write about technology, digital business, AI, and engineering practices for teams committed to execution excellence.