You can probably say what makes your company different in one sentence. Whether your company's differentiation is real comes down to three checks: a competitor saying the same thing, a well-funded team copying it inside a product cycle, and a set of numbers that either move or stay flat. Most of the differentiation lines I am shown fail at least one of the three. It matters most as you scale: in my experience a differentiator three founders could feel in the room thins fast once fifty people are making decisions none of them discussed with each other. Here are the three checks, and a test you can run on your own company this week.
The competitor test
Start with the sentence itself, the one you use to describe what makes your company different. Read it back as if you were the competitor you respect most. If they could say the same sentence about their own company, and a customer would nod along either way, the sentence describes the category you both compete in. Phrases like "we put the customer first" or "we work harder than anyone else" pass this test for nobody, because every company in the category says them and customers have learned to read past them. Flowdonia's own method, Differentia, starts with the Cast: the few distinctive attributes worth committing to, each one named, owned and concrete enough to build on, with evidence a reader could check. The competitor test is the first check a Cast has to pass.
The copy test
Passing the competitor test only proves the differentiator is not shared today. The next question is whether it can be copied. Investors have a word for a differentiator a competitor cannot easily reach: a moat, an advantage a rival cannot simply reproduce. A more formal version of the same question is Jay Barney's VRIO: is the differentiator valuable to a customer, is it rare across the category, would it be costly or slow for a competitor to copy, and is your company organised to use it. That last question is where I see most claimed advantages fail. A capability that is valuable, rare and hard to copy still produces nothing if the team that owns it is not set up to act on it. A clever feature is usually copied inside a product cycle. A position built over years, one a whole category defines itself against, is a harder thing for a copier to reach.
The numbers test
A differentiator that passes the first two tests still has to clear a third. Look at what a customer does: what they pay, which option they reach for first, and how long they stay. A real differentiator shows up as a customer paying more without hesitating, choosing you ahead of a cheaper option, or staying with you well past the point they would normally start shopping around. A satisfaction score on its own is not enough. It only counts once it connects to a number your finance team already tracks: price, share of preference, retention, or the cost of winning a customer in the first place. If none of your numbers move when the differentiator is present, you have a claim and no evidence.
I led design on the consumer philips.com redesign, which lifted NPS by 12 points. That number only mattered because it was tied to what the business could see: the same work carried a €4M a year effect. A satisfaction score that connects to nothing is the thing this test is built to catch.
A test to run this week
Write down the one sentence you use to describe what makes your company different. Then run it through the three checks above, in order, using people who did not write the sentence. Nobody who wrote the sentence can mark their own test.
Give it to someone who knows your closest competitor well, ideally a customer who considered both of you, and ask if the sentence could describe either company. If it could describe either company, go back to the start. If it could only be yours, you have the sentence.
Price out what it would cost a well-funded team to copy whatever survived: the specialist hires, the technology, the time it would take. If a well-resourced rival could reach the same place inside a product cycle, the differentiator is exposed, whatever it feels like from inside your company.
Pull the numbers last. Choose one metric, a price point, a win rate against a named competitor, or retention measured past the point where customers in your category usually start shopping around, and check whether it has moved in the direction the differentiator predicts. If it has not moved, or nobody has checked, you have your answer.
What it looks like when a differentiator lands
I led the go-to-market design for Philips OneBlade. It launched under the line "this is not a shaver", which I do not think any other razor brand could have put on its own box and meant, and it reached €55 million in its first year, in a category that had not existed before it.
Flowdonia runs these three checks as Get sharper, back within the week. Decide how you show up is the two weeks that follow when the sentence still needs deciding.