What nobody tells you about becoming CEO.

"I'm ready. I'm built for this." Then the reality.

Fiona McKenzie spent 12 years at the B2B marketing agency River, rising from account director to CEO, and then led the business through its sale to Marketbridge, where she became managing director for Europe. When the chance came to take over from the founders, she didn't hesitate.

I was like, I'm ready. I'm built for this. Let's go. And then I actually stepped into the role and had the reality of it.

What surprised her wasn't the workload. It was how different the seat felt. Even when you sit on the leadership team and help shape decisions, being the CEO is not the same. Your mindset changes. You see things through a different lens. People say it's lonely at the top, and Fiona found they were right. She admits she went in a bit naive, chasing the next step and the value she could see herself adding, and then had to learn the job while doing it.

I hear this from CEOs all the time. Promotion into the top job is one of the few moves in a career where nobody can fully prepare you, because nobody else in the building has done that job in that business.

Your old strengths will get in your way

When I asked Fiona which habits made her excellent before she became CEO and then became liabilities, she was honest. She had been very hands-on. She loved customer experience and thrived on fast responses and pitches that landed. Stepping back and letting the person who took over her old team do things their own way was hard.

Her biggest lesson in year one was that she didn't need to be involved in everything. Her job was to create a vision and a framework for success, and then give her leadership team the autonomy to run the business day to day.

She now measures herself with a simple test:

Can I go on holiday for a week without writing a handover to anyone? If the answer is yes, then I'm doing my job successfully.

It's a good test for any CEO. If the honest answer is no, the business isn't yet built to run without you, and that's a strategic risk as well as a personal one.

Fiona also said something I didn't expect. Coming up through the organisation can be a hindrance as well as a help, because you know too much. You arrive with assumptions from your old role that may not be right, and part of being a good CEO is not getting caught in the detail.

Build your own board

Most CEOs I speak to say they need to step outside the business to move it forward, and then say they're too busy to do it. Fiona had a straightforward answer. Knowing she had never done the job before, she joined Vistage, a CEO peer network, and committed to one day a month out of the business with a group of leaders from completely different sectors.

She was sceptical at first. How could people who didn't understand marketing help her? It turned out that was the strength. They validated what she was doing well, showed her which problems shouldn't keep her up at night, and gave her somewhere to take things she couldn't raise with her own leadership team. And sometimes they told her what she needed to hear but didn't want to.

You don't have to use that particular network. The point is having people outside your organisation who will hold you to account and tell you the truth. The loneliness of the role is real, but it isn't compulsory. You have to be intentional about building the support around you.

The decisions that won't make you popular

Like many agencies, River grew fast after COVID, hired, then hit a slump and had to restructure and cut headcount. Fiona described delivering that message after years of building a culture as one of the hardest things she has done as a leader.

You do sometimes have to make those decisions that you know won't be popular, but ultimately it is about having the respect of your team. They might not always like the decisions you're making, but you have to make sure that you're being fair.

She chose to let her guard down in moments like that. She'd tell the team she knew it was the right thing to do, and that it wasn't easy. She also knew when a moment called for a strong message even if she felt differently inside. Getting that line right is a judgement call, and it gets easier once you're comfortable with who you are as a leader.

Culture is built in small moments, not all-hands meetings

When I asked Fiona what one truth she'd tell herself on her first day as CEO, it was this: leadership isn't built in frameworks and plans. You can't just launch big initiatives and run nicely scripted all-hands meetings. You build culture through the small interactions in the office, the handwritten note, the recognition post.

Her team used a weekly employee engagement tool so she could see how people were feeling in close to real time, and she treated the feedback as something to act on, not a report. When the answer to a suggestion was no, she explained why. Her view was that if you can't answer the questions and concerns your people have, they will never connect to the vision you're presenting.

That's the shift I see in CEOs who do well. They stop thinking of strategy as something they write alone and start seeing their role as connecting the dots between the insight their people already have.

Knowing when to sell, and what it costs you

Fiona wasn't a founder, which she thinks gave her a kind of superpower when it came to the sale. Each year as she wrote the strategic plan, she could see the business could keep growing organically, but not fast enough to deliver everything she knew it was capable of. What had got River to that point wasn't going to take it to the next phase.

The process itself was a wild ride. She ran the business day to day, kept the culture going and kept innovating, while negotiating with buyers and going through due diligence that nobody else in the business could know about. And she knew the hardest work would begin on the day the deal closed: standing in front of her people, explaining the decision, and being more present than ever in the months that followed.

Then came another shift. In the new organisation she was no longer the CEO, and many decisions she would once have made sat with other people. She was clear that you can't make that decision based on your ego or your career. You make it for the business and the people in it.

If you're stepping into the role

What I'd take from Fiona is that the seat will feel different however close to it you were. Work out early which of your old habits the role doesn't need, because some of them will be the reason you got the job. Find a peer group outside the business and guard the time, since the diary will always offer a reason to skip it. When the unpopular call comes, make it fairly and admit it's hard. And try the holiday test in your first year rather than your fourth.