How to Test Strategic Assumptions Before Committing

How to Test Strategic Assumptions Before Committing

Most strategic failures in financial services are not failures of execution. They are failures of assumption. The deal model assumed deposit beta would stay below 40%. The product launch assumed advisers would recommend it. The expansion assumed the regulator would treat the new entity the same way as the parent. None of these were tested seriously before the commitment was made.

Testing assumptions properly is harder than it sounds, because the assumptions that matter most are usually the ones nobody has written down. Here is how to do it well.

Surface the assumptions that actually carry the decision

Start by separating three categories: facts (verifiable now), forecasts (claims about the future), and beliefs (claims about how people or institutions will behave). The third category is where most strategic decisions break.

Force the team to write each load-bearing assumption as a falsifiable statement. Not "the market is attractive" but "we can acquire 80,000 customers in 24 months at a CAC below £140." Not "the regulator will be supportive" but "the FCA will authorise the entity within nine months without requiring ring-fencing."

Then rank them by two criteria: how much the decision depends on each being true, and how confident you actually are. The assumptions in the top-right, high dependency and low confidence, are the only ones worth testing intensively. Everything else is noise.

Design tests that can disconfirm, not just confirm

The most common error is building a test that can only return a positive result. Customer research that asks "would you be interested in a product like this" will always produce encouraging numbers. It tells you nothing.

Good tests have a pre-declared failure condition. Before you run them, write down what result would cause you to stop or change course. If you cannot articulate that, the test is theatre.

For each high-stakes assumption, pick the method that fits:

• Behavioural assumptions (will customers switch, will advisers recommend, will counterparties accept new terms): use small, real-money pilots or structured interviews with people who have actually made the decision before, not people speculating about whether they would.
• Regulatory and political assumptions: do not rely on your government affairs team's read. Triangulate through former regulators, sector counsel who have run the specific process, and informal soundings via trade bodies. If three independent sources give the same warning, treat it as signal.
• Competitor response assumptions: war-game it with people outside the deal team who have an incentive to find holes. Internal teams committed to the strategy will reliably underestimate competitor reaction.
• Operational assumptions: ask the people who will have to deliver, not the people who designed the plan. The gap between these two groups is usually where the assumption fails.

Sequence the tests by cost of being wrong

Test the assumptions with the highest cost of being wrong first, even if they are harder to test. Most teams do the opposite, running cheap tests on minor assumptions because they produce quick wins for the steering committee. This builds false confidence.

If the entire strategy depends on a regulatory outcome or a single anchor client, that assumption is tested first, before the surrounding work proceeds. Otherwise you are building a structure on a foundation you have not checked.

Watch for the signals that you are fooling yourselves

A few patterns repeat:

• The assumption keeps getting reworded as it fails tests, rather than being abandoned.
• The people raising doubts get reframed as "not commercial" or "not aligned."
• Evidence against the assumption gets attributed to one-offs, while evidence for it is treated as structural.
• The decision date is fixed before the testing is complete, so tests get rushed or skipped.

If you see two or more of these in the same process, the testing has stopped being real. Pause and reset before continuing.

Decide what "enough evidence" looks like, in advance

Before testing begins, agree with the decision-makers what evidence would be sufficient to commit, what would require a smaller commitment with optionality, and what would mean walking away. Documenting this in advance is the single most useful discipline available, because it prevents the goalposts moving as the team becomes more invested.

Your next move

Take the decision currently in front of your board or executive committee. Write down the three assumptions it most depends on, in falsifiable form. Then ask: what test, runnable in the next 30 days, could prove each one wrong? If you cannot answer for any of the three, you are not ready to commit.