Go, even if it's ugly.

His core directive is a bias to action over analysis. A good decision made fast usually beats a perfect one made late, and the fear of looking foolish is what keeps most people on the board, never jumping.

"It's like being on a diving board… I wouldn't be afraid of failure. Go, even if it's ugly. It's worth it."

His advice to anyone with an idea is blunt: "Just make it happen. Don't spend too much time thinking." His motto for failure: dust off, and go again.

Where Western incumbents see a list of reasons a country is too hard, O'Brien sees the opening. The lens is everything: lead with the upside, because everyone else is already leading with the risk.

"We look at the world as a market and say, 'Where are the opportunities?' and we just go for them. We don't look for the problems."

His view is that American and European firms forfeited whole continents this way, while investors who simply chased the opportunity "stole the march."

O'Brien built Digicel where rivals would not go: Jamaica, Haiti, Papua New Guinea. The thesis is simple arithmetic. An underserved market has nowhere to go but up.

"If a market is only 50, 60 percent penetrated, the opportunity is to get to 100."

The forecasts undershot reality: "When we went into Papua New Guinea, we thought we'd get 200,000 mobile users. Today we have 2.4 million." The empty ground was the opportunity.

Digicel rolled out at a pace incumbents could not match, at one point launching a new market every three months, and took two-thirds of Jamaica within two years. A fast rollout is not just growth; it is a moat.

"At one stage we were launching a new market every 3 months."

The boldness ran on rigour, learned from his mentor Tony Ryan: attention to every detail, and the expectation that tasks get done quickly.

O'Brien runs a portfolio and lets the winners run. The aim is not to be right every time; it is to be right often enough that the few that come home pay for everything.

"If you get two-thirds of your investments right and some of them really come home, it's a result."

As he puts it, "sometimes donkeys can become thoroughbreds. That's the nature of a portfolio approach." His one-word principle: keep going.

O'Brien prunes ruthlessly toward growth, and is candid about the cost of forgetting it. His own worst mistake was a low-growth, declining sector.

"Running a business that is growing by 25 per cent is exciting. I would sell a low-growth business."

The lesson is told against himself: "I invested €500 million in a newspaper business and it's worth 20 per cent of that today." Do not stay in an industry that is dying.

In frontier markets, O'Brien treats visible local good as a condition of doing business, not an afterthought. It is also the smartest brand and licence-to-operate strategy there is.

"If you're a major multinational and you don't do something decent in a country but you make a substantial profit, you're a gobshite, basically."

The Digicel Foundation built roughly 175 schools in Haiti. Setting it up fast, he has said, was "probably the best thing we ever did."