A decade on, Norris says he “not surprised at all” to see Comyn, 42, this week named as the next chief executive of Australia's largest company. But while it might not have been a surprise to Norris, chairman Catherine Livingstone’s decision to appoint a banker who has spent almost all of their career at CBA did come as a shock to some observers. Although Comyn had been seen as an internal favourite to replace Ian Narev, a key backer, many assumed his shot at being CEO was all but quashed by the money laundering scandal that engulfed the bank last August. It was assumed the Livingstone-led board would instead recruit a banker from outside CBA, potentially overseas, to shake up its culture and rebuild its tarnished reputation after a series of scandals. So how did Comyn rise up within the ranks to take on the challenge of winning back the public's trust in CBA?

And how might the 20-year insider navigate the challenges he faces at the country’s biggest, but also most scandal-prone, bank? CLIMBING THE LADDER Comyn joined CBA in his mid-twenties, but his background was not in finance. After growing up in Sydney, Comyn studied aviation at the University of NSW. He didn't initially intend to become a banker, and briefly worked in an aviation business before joining CommSec in 1999, as the bank spotted the opportunity to bring low-cost share trading to the masses via an online platform. Paul Rickard, the founding managing director of CommSec, helped recruit Comyn to the online stockbroking business, as the bank was looking for young staff outside the traditional finance sector.

"We were looking for people with a strong background in maths or science, and the right type of demeanour," says Rickard, now an independent director. Within seven years, Comyn had risen to be managing director of CommSec, which was grabbing market share as online financial services took off. By the time Comyn was leading CommSec, Rickard was chair of the online stockbroker, which was CBA’s biggest digital business. He says Comyn made an impression on people at the top levels of the bank as the stockbroking unit made some important acquisitions, and Comyn led the response to problems stemming from the collapse of Queensland financial adviser Storm Financial. Storm went bust in the global financial crisis after advising clients to borrow against their homes to invest in shares. CBA, a key lender to Storm clients, admitted to "shortcomings" in how it lent money to some Storm clients, which led to it paying out compensation.

"Matt got to the bottom of that, and I think it made a very good impression," Rickard says. Bank insiders point to Comyn's role following the Storm collapse as an example of his willingness to "get his hands dirty" in response to problems – a quality that has been highly valued as CBA has faced explosive allegations it breached anti-money laundering laws. Comyn also earned some credit for the rise of CommSec - which remains the dominant online retail broker. Rickard adds that Comyn works "incredibly hard," including putting in long hours. "I would think I've probably never met someone who works harder than him." Significantly, in this role Comyn also reported to Narev, who was running the business and private banking division, and went on to become CEO in 2011. He remained a key internal backer of Comyn, who will replace him in April. Known for being highly ambitious by colleagues, Comyn was briefly lured from CBA to Morgan Stanley Smith Barney in 2010. But within only about six months, he was brought back to CBA by Narev and Norris.

“I think the key moment in his career was when he decided to come back from Morgan Stanley to the Commonwealth Bank,” Norris says. “I would imagine that would have been a reasonably stressful time for him, having left the organisation, and then finding that it wasn’t what he wanted. "I think he saw the opportunities for him at the Commonwealth Bank were significantly better.” As the newly-appointed CEO Narev settled on his executive team in 2012, Comyn was then appointed at the age of 36 to run the engine room of CBA, its vast retail banking operations. To some observers in the industry, it looked like brave appointment. His predecessor Ross McEwan was more experienced and had left CBA after missing out on the top job to Narev, and he now runs UK giant Royal Bank of Scotland.

In the five years since, the retail bank has been CBA’s star performer, raking in almost $5 billion in profit last year. The share of CBA profit that has come from Comyn’s division has swelled from 40 per cent to 50 per cent over this period. I would imagine that would have been a reasonably stressful time for him, having left the organisation, and then finding that it wasn’t what he wanted. Ralph Norris, former CBA CEO While the business has boomed thanks to a surge in credit growth and very few borrowers defaulting, Comyn is credited with building on the bank's CBA's two critical goals: leadership on technology, and on customer service. "It’s very easy to coast with a business that has obviously performed well over the past decade, but the decisions he’s made have been about enhancing and improving that performance,” Norris says. While the bank's reputation has been dragged through the mud in recent years, the closely-watched Roy Morgan measure of customer satisfaction has consistently put CBA ahead of rivals.

CBA’s retail arm employs the biggest share of CBA’s 45,000 staff, and former colleagues say Comyn comes across as approachable and down-to-earth in his manner with staff. He is not known for being particularly bubbly or outgoing, and is seen as perceptive, detail-oriented, and dedicated to the company. Given his focus on the complex details of the business, it is suggested by some that he will need to delegate more once he takes over from Narev. Outside the world of work, Comyn is married with three children and lives in Randwick, in Sydney's eastern suburbs, and is keen on fitness including cycling and skiing. At 42, Comyn is young by the standards of most major bank CEOs - though former National Australia Bank chief Cameron Clyne was just 40 when he was appointed to the job. Former CBA director Harrison Young says: “He is 42 years old, but he has great maturity. He is very very smart, but you don’t get the impression he thinks he is very, very smart.”

Young, who left the CBA board in November, says Comyn's appreciation of the social and political context in which banks operate will stand him in good stead for leading CBA as it faces challenges including the royal commission, a prudential inquiry and legal actions from regulators. “Many would see managing six different streams of inquiry and litigation as an impossible job. He and Catherine will do it very well,” Young says. Challenger executive Ian Saines, who previously worked alongside Comyn at CBA, describes Comyn as easy-going, with an ability to get along well with people. Large corporations such as banks can be highly political, but Saines says Comyn would win people around based on logic and his command of the facts. “He’s got humility as a leader, and he relies on credibility over personality," Saines says.

Saines is chief executive of Challenger's funds management business, and worked alongside Comyn as a senior executive at CBA from 2004 to 2013 leading its institutional banking and markets division. On top of managing the internal running of the bank and satisfying investors, however, one of Comyn's biggest challenges will come from external forces, such as the royal commission into financial misconduct. Yet bankers who know Comyn say he is well aware of how bank decisions can have major consequences not just for customers and investors, but also the wider community. Jason Yetton, who was Comyn's opposite number at Westpac where he previously ran retail banking, says Comyn considers the broader responsibilities of a bank, beyond those to shareholders, customers and staff. “What I always found is he was someone who did not shirk the kind of questions that come from all stakeholders on what you should do,” Yetton says.

CHALLENGES AHEAD Comyn’s appointment was generally backed this week by stock-broking analysts, who point to his strong record for delivering financial results. Livingstone also emphasised a key task facing Comyn was to maintain the bank's financial "momentum," and to deal with the looming threat from technology-based rivals eyeing the bank’s hefty profits. The most immediate challenge he may face, however, will be to rebuild public trust in CBA after the tumultuous few years. Public discussion of banks is likely to soon be dominated by the royal commission into misconduct, an area where CBA has had more problems than peers, and a powerful review of the CBA's governance and culture, due to report findings in April. Comyn has had some taste of being grilled by politicians, appearing alongside Narev at last year’s House of Representatives committee banking inquiry, but the scrutiny this year promises to be far more intense. Unlike an "outsider" CEO, Comyn may get little in the way of a "honeymoon" period as CEO, observers say.