Nobody doubts that getting to the Olympics as a competitor is a difficult feat. There are the hours of relentless training, the gruelling qualifying criteria, the personal sacrifices, and of course, the possession of a rare athletic talent required to even contemplate competing at such a level in the first place.
Combine all that with the requisite personal drive plus the right combination of access to good diet, effective coaches and appropriate training facilities and, with a knock on wood and a touch of good old-fashioned "right place, right time" luck, there's every chance a shot at the Games can come into sight.
In pics: Olympians who overcame adversity
On the other hand, some athletes have made it to the Games and triumphed when circumstances have not been so kind; when life's great lottery has conspired to give them the short end of the stick and place them even further behind your average Joe. These are the athletes who have not let the rough hand of fate stand in the way of them and victory athletes who with dedication to training, diet and a sheer will to win have refused to bow to life's setbacks. These athletes have beaten the odds, and fellow competitors, to reach the top of the world.
The beauty of the Olympics is that they do not discriminate. Provided an athlete has talent and their path has led them to Olympic selection, they may stand side by side with other hopefuls, no matter their personal circumstance, be it fortunate or adversity.
Take Haile Gebrselassie (pictured above), one of a family of 10 children from an impoverished Ethiopian mountain village who rose to become a legend in the 10,000m race; think of Cliff Meidl, the American Olympic kayaker who suffered severe burns, the loss of two toes and the near-loss of his leg after a construction accident at age 20; consider Aussie swimmer Keiren Perkins, who only took up swimming for rehabilitation after a severe leg injury caused by running through a plate glass window at the age of eight.
Then there are the likes of legendary Finnish runner Paavo Nurmi, who won a total of nine gold and three silver medals at Olympics from 1920 to 1928. From the austere Finnish coastal town of Turku, Nurmi was born in poverty as the eldest of five children. The family lived on a diet of black bread and dried fish, with fresh meat and fruit only an occasional treat, and the children had to walk many miles to school each day often in the snow-bound depths of the long Finnish winter.
Such an upbringing spawned a runner of such sheer dogged determination that no one could come close to him in his prime and, in 1958, when reflecting on his career, he said that this early life had taught him that there are "neither unbeatable records nor human limits".
Another Olympian to sensationally overcome adversity is American Greg Louganis, often said to be the world's best diver. Louganis who was given up for adoption by his teenage parents when he was eight months old took up diving as a child because his doctor suggested exercise might assist his allergies and asthma. He went on to win a round of world titles and Olympic medals but was diagnosed with HIV just six months before the 1988 Seoul Olympics. At the time, HIV was not well understood and Louganis was promptly dropped by all of his sponsors bar Speedo. Despite the shock of the diagnosis, the exiting of his sponsors and splitting his head open during preliminary rounds resulting in a concussion, Louganis went on to win two gold medals at Seoul.
At this year's London Games, as in other years, there is any number of stories of athletes winning out over adversity. One is the extraordinary Monique Newton.
The diminutive power-lifter from London battled brain cancer as a child, undergoing chemotherapy and radiotherapy, and then later suffered severe depression that led to a suicide attempt at age 15. But after pulling her life together, the 48kg dynamo discovered powerlifting and thus her life's focus.
"I took up powerlifting because I wanted to do something where I would be the underdog and have to push myself to get to the top," she has said. "It makes me feel happy to know I can use my story to help people who are or will be in a similar situation."
Such a sentiment is perhaps characteristic of those who have found the odds stacked against them and yet have ploughed ahead to success. Winning gold at the Olympics takes a special kind of brilliance and sometimes winning life's greater battles is the best training possible for such a theatre of extreme competition.