What is the difference between Sebastian Vettel and Tony McCoy? Or Vettel and Ryan Giggs and Sachin Tendulkar? They are all serial winners and model professionals at the highest levels in their chosen sports.
Or have been.
Tendulkar is approaching the end of an amazing cricket career littered with statistical landmarks.
Giggs is slipping gently into a coaching role at Manchester United and Tony McCoy's wife has, jokingly, suggested that after riding 4,000 winners it is time for her to cut up his licence.
Vettel, however, remains a very young man and, at 26, obviously has a decade of continued Formula One motor racing ahead of him.
He has not yet reached his peak and he has no plans to relent in his insatiable assault on the record books.
Only a few weeks ago, having won the Indian Grand Prix, he joined an elite club of four-time world champions.
Ahead of him now lie only the achievements of the sport's legendary greatest drivers, Michael Schumacher and Juan-Manuel Fangio.
Yet there are those who carp at his feats. Some claim that Vettel must leave his triumphant Red Bull team which has won four consecutive teams' titles in step with the young German's reign of supremacy.
This week even the highly-respected voice of three-time world champion Jackie Stewart was heard decrying Vettel's claims to be one of the greatest of all.
His view was that Vettel had to move to prove himself in more adverse conditions, as Schumacher did in winning five titles with a previously-forlorn Ferrrari after winning two at Benetton.
It was a view that Red Bull motorsport advisor Helmut Marko said he could not take seriously.
Vettel himself was more fulsome on the subject when he was questioned during a celebratory visit to Red Bull's Milton Keynes base.
"I think that even if I go to another team I will still have my doubters," he explained, when asked if a move would sway his critics.
"I don't think it will change people's opinions. At the end of the day, you have to be happy with yourself, and right now, I am happy where I am given what we have achieved."
Asked whether he felt tempted to line-up alongside one of his main rivals, as Ayrton Senna did with Alain Prost at McLaren, Vettel added: "As a driver you always try to be with the best team.
"If you look back in F1 history, you will see that the best drivers have nearly always won races and championships with the best teams.
"I'm very happy where I am and it's about you, and whether you are happy with who you are and if you can look at yourself in the mirror. I'm not thinking about anywhere else, or racing with anyone else."
Vettel believes the perception of him dominating races and championships is unfair and has contributed to a lack of fanfare surrounding his fourth world crown.
"Some people like to call it 'domination', but I don't like that because it makes it sound like it's easy to be winning," he added. "If we look back to every single race, it was hard work and we had to put everything in it.
"We've had great results in circumstances where perhaps we shouldn't have done. Perhaps the races have lacked excitement, but when you know yourself what you have done -- with all the effort that's gone in at the factory -- it's a great feeling."
As he settles in to his Texas hotel next week ahead of the United States Grand Prix, he may give it little further thought.
He is a serial winner and he wants to drive the fastest car -- just as McCoy wants the fastest horses.
In their sports, it is all about winning. And Vettel, with Red Bull, is the standard setter. It is up to the others to catch him.