Hey folks - Firas here.
This week’s PMF Playbook comes from my episode with Cosmin Nicolaescu, Co-Founder and CEO of Accrual.
Cosmin has had one of those rare Silicon Valley journeys: Microsoft, Stripe, Brex, and now founder. He has seen massive companies, high-growth startups, and hyper-scaling cultures from the inside. But what made this conversation valuable was not just his resume. It was his honesty about what changes when you become the founder.
The biggest shift is simple: you lose optionality.
An employee can decide the company is no longer right for them and move on. A founder cannot do that so easily. The more people join, the more customers depend on you, the more investors believe in you, the more locked in you become. Every hire adds responsibility. Every customer adds obligation. Every decision starts to carry more weight.
That is the part of founding that people romanticize less often.
Let me walk you through what stood out.
The founder burden: responsibility compounds
Cosmin described founding as lonely, not because you are physically alone, but because you are constantly balancing different time horizons.
Investors want growth. Employees want momentum and meaning. Customers want features, reliability, and value as quickly as possible. And the founder has to hold all of that at once while still making decisions that keep the company alive and moving forward.
That is a different kind of pressure from being an operator.
At Microsoft, Cosmin was one engineer among many. At Stripe, he saw what great culture looked like in a high-growth environment. At Brex, he stepped into a much larger leadership role, leading engineering without the same safety net.
But founding Accrual introduced something else entirely.
When someone joins your early company, they are taking a real risk on you. Cosmin said every person who joins adds a little more stress, because each person is betting part of their career on the company’s vision.
That is the emotional weight of founding.
The regret framework: why inaction can be worse than failure
When Brex came calling, Cosmin was happy at Stripe. He was growing, building important products, and working with great people.
But he knew that one day he wanted to lead engineering at a company without a safety net.
So he used a regret minimization framework.
If he stayed at Stripe and Stripe did well, that was fine. If he joined Brex and Brex did well, that was great. If he joined Brex and it failed, he would lose time but learn from the experience.
The worst outcome was staying at Stripe and watching Brex become huge without ever knowing what he could have learned by taking the leap.
That is a powerful career lesson.
Action teaches you something. Inaction only leaves you wondering.
Why accounting passed the founder-market fit test
When Cosmin and his co-founder started exploring what to build, they looked across many industries. They were optimizing for two things: impact and learning.
Accounting passed the test because it sits at the backbone of business. Every dollar that moves has to be accounted for. Yet the industry remains deeply manual, with accountants spending huge amounts of time on mechanical, repetitive work instead of strategic judgment.
They also saw a market under pressure.
Fewer people are becoming CPAs. Many accounting firm partners are aging. Firms want to grow, but they cannot hire enough people. At the same time, accountants care deeply about doing right by their clients.
That passion for the craft resonated with Cosmin.
This is an underrated founder-market fit lesson: you do not just need to like the problem. You need to like the people you are serving. If you do not enjoy spending time with your customers, the journey becomes much harder.
Founder-market fit as a lifestyle choice
One of the most interesting parts of Cosmin’s story is that he and HIS Co-Founder did not just study accounting from the outside.
They took CPA classes at community colleges.
That is not founder-market fit as a talking point. That is founder-market fit as a lifestyle choice.
Their reasoning was simple: they could not replicate decades of CPA experience, but they could at least understand the baseline knowledge of someone entering the profession.
That depth matters.
Without it, it is easy to oversimplify a complex industry. Accounting can look mechanical from the outside. But once you go deeper, you see the nuance: judgment, planning, trade-offs, regulation, client context, and strategic decision-making.
The PMF lesson is clear: if you want to transform an industry, first respect it enough to learn its language.
Accrual: creating time for accountants
Accrual works with some of the largest accounting firms in the United States.
The problem they are solving is time.
Accountants spend too much of their day on tactical, mundane, mechanical work. Accrual removes as much of that work as possible so accountants can spend more time on what actually matters: helping clients make better financial decisions.
Cosmin described the mission as creating accountants out of thin air.
Not by replacing accountants, but by giving firms back massive amounts of capacity.
That is the right AI wedge in a professional services market. Not “replace the expert.” Instead: remove the work that prevents the expert from being an expert.
The customer lesson: acquisition is not the win
Cosmin made a point that every founder should sit with:
Customers are the only thing that really matters.
You can fundraise without customers. But that does not mean you have a business.
The first signal is that you can acquire customers. The second is that you do not lose them. The third, and maybe the most powerful, is that customers start pulling you into new directions.
That means they trust you. It means your product is landing. It means they see you as a partner, not just a vendor.
But Cosmin also warned against a common founder mistake: over-optimizing for growth.
Some founders treat customers as acquisition logos. They win the deal, celebrate the growth, and move on to the next one. But trust is earned slowly and lost quickly.
In accounting especially, change management is hard. If accountants are spending most of their day in your product, the experience has to be excellent. Otherwise you are not improving their work; you are making their day worse.
The lesson here is simple: landing the customer is not the finish line. It is the beginning of the obligation.
The real founder transition
The deepest difference between operator and founder is not decision-making, speed, or even ownership.
It is responsibility.
As an operator, Cosmin cared deeply about building good teams and being a strong leader. But as a founder, the stakes feel different. If the company fails, it is not just a business outcome. It affects the people who took a risk to join.
That responsibility compounds with every hire.
And that may be the clearest sign of founder maturity: understanding that the company is no longer just your ambition. It is now other people’s risk too.
Closing thought
If I compress the entire episode into one sentence, it’s this:
PMF is not just about finding a painful market; it is about earning enough trust to remove real work from customers’ lives without disrespecting the craft they have spent years mastering.
Accrual is not trying to make accountants irrelevant.
It is trying to give accountants their time back.
And in a world where every professional services firm is under pressure to do more with fewer people, that may be one of the most valuable products you can build.
Until next time,
Firas Sozan
Your Cloud, Data & AI Search & Venture Partner
Find me on Linkedin: https://www.linkedin.com/in/firassozan/
Personal website: https://firassozan.com/
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