His dissatisfaction could stem from the way he looks at his success.
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He spoke of his joy at his success at Lee Valley, and how failing to qualify for the 2008 Olympics in China had spurred him on.
One day, I found myself sitting in the bar in the Hotel Claridge with a little old man called Juan Carlos Borges, who was astonished at my interest in his work and at its success in Brazil, given that it had been years since he had published one of his brief botanical poems.
Mickelson, who is on course for his third success at the event (his last victory coming back in 2005) is wary of the threats and is taking the positives out of two frustrating finishes.
Yet his conviction on insider trading charges proved that at least some of his success had depended on illegal, unethical acts.
But few could begrudge Webber his belated win, repeating his 2009 success at the same circuit and his seventh career triumph in F1.
Lee Iacocca drove Henry Ford II nuts at Ford, but his track record of success at Ford included the legendary Mustang, and when he was fired and then made CEO at Chrysler, he implemented ideas that Ford had rejected chief among them, the minivan.
However, his time at Leeds was not a success and he lost his job in December 2008, just 11 months after his appointment.
His success at Audi, a key profit engine, propelled him to his current position.
Jack Welch attributed his success at GE to spending the bulk of his time on people issues.
His success at the Den led to his return to Highbury, replacing Don Howe as manager in 1986.
Castro-Wright was a popular figure within Wal-Mart, and hailed for his success at Wal-Mart de Mexico, according to the Times.
His success at Alco led to him running the factories of Buick, then the biggest part of the struggling young General Motors.
His success at introducing liquid Tide in 1992 won him an assignment abroad: heading up the Far East operations, then 10% of total revenues.
"I play well here -- and that's as simple as it gets, " Woods replied when asked the secret of his success at Bay Hill.
Mr Dearman, who also invented the MicroVent resuscitation device used in ambulances, told BBC News he was delighted at the success of his ideas.
But it's clear Gardner views himself as a natural center fielder, one who will never be as fluid in left field, despite his success at the position.
Tebow is a legend in Florida thanks to his success at University of Florida where he won the Heisman Trophy and led the Gators to the 2008 national championship.
The 28-year-old is arguably the form player on tour after his success at the ATP World Tour Finals last November and in Doha to start the year -- where he beat both Federer and Rafael Nadal.
The newly elected Philippine president, Joseph Estrada, is a walking model of the perceived evils of populism: he owes his success at the polls more to his past as a film-star than to any technocratic expertise.
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Apart from his success at Old Trafford, Ronaldo is a regular figure for his national side, making his full international debut in 2003 and going on to represent Portugal at the 2006 World Cup and Euro 2008 finals.
At the height of his success Sean Quinn Sr employed more than 8, 000 people worldwide, but the majority of the jobs were based near his home, bringing much needed employment to the border counties of Fermanagh and Cavan.
They drove to Firoza, to a private clinic there, run by a mere pharmacist, who nevertheless kept a huge clientele because of his abrupt and sure manner and his success at healing all the prevalent diseases with the same few medicines.
His success at Santos has also made Neymar the biggest star on the Brazilian national team and he had previously said he wouldn't move to Europe until after the World Cup in Brazil in 2014, when he will carry the hopes of the host nation as it seeks to win the tournament for a record sixth time.
After being elected Yorkshire President following his success at Saltley, Scargill became NUM President in 1981 and the scene was set for the 1984 dispute when, in defiance of the government's demand that 20 uneconomic mines should be closed with the loss of 20, 000 jobs, the strike went ahead without the endorsement of a pit head ballot.
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But it was during his time at Chelsea where Clarke achieved most of his success.
Duffield started his first big success, PeopleSoft, at age 47, mortgaging his house to fund what was his fourth startup.
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