Consistency is a vexed subject in cricket. Almost anyone can be accused of inconsistency; the perfectly consistent player is yet to be born, because failure, especially for batsmen, is hardwired into the structure of the sport. Consistency is also deceptive. I finished most first-class seasons with about 1200 runs. Consistent? Not really. Within each season, I was prone to unusually large fluctuations in form.

That point was brought home during a chance conversation with an opposition coach in 2004, just after Warwickshire had won the championship. The coach singled out the contribution of Jonathan Trott, who had made 1200 runs, averaging over 50, with only one hundred but ten fifties. Conventional wisdom held that Trott had a poor "conversion rate". The coach took the opposite view. "From the team's perspective, I can't think of a more useful way to divide up 1200 runs." I couldn't help thinking of the flaws in my own season: I'd scored exactly the same number of runs as Trott, but with a completely different distribution. My season consisted of two patches of high scores, separated by long stretches of disappointment. I'd reached the same destination via a very different journey. Twelve hundred runs at 50 might sound "consistent", but the headline numbers can mask serious inconsistency below the surface.

The same question applies to cricket at all levels, from club to Tests. Is it better to achieve consistent high competence or transient dominance? The answer depends partly on perspective. Fans, I suspect, tend to remember players who achieve moments of brilliance rather than grinding reliability. But within the team, I suspect, the opposite is true. Team-mates like to know what they're getting. The question of how to measure achievement also reveals a deeper divide in sport. We will come to that later.

Statisticians argue about how to measure consistency (on ESPNcricinfo alone, S Rajesh and Gabriel Rogers offer differing methodologies). Sometimes the statistics reinforce our instinctive judgements. A snap judgement about Brian Lara and Jacques Kallis would contrast the instinctive, mercurial West Indian with the methodical, controlled South African. And the stats confirm our hunch. One statistical measure found Kallis to be the most consistent player of all time, and Lara to be the fourth most inconsistent.

Where does Sachin Tendulkar fit in? Lara, obviously, owns the record for the highest score in both first-class and Test cricket. In contract, Tendulkar has made more runs and more hundreds than anyone else. You could argue that Lara climbed the higher peaks but Tendulkar covered much more land. If you wanted to own a stock or a share, buy Tendulkar. But for moments of total mastery - I'm thinking especially his two back-to-back, match-winning hundreds against Australia in 1999 - it's hard to look past Lara.

The same pattern is revealed in other measures of consistency. Lara's career shows slightly more volatility. S Rajesh informs me that Tendulkar has played 64 series. In 21 of those (33%), Tendulkar has averaged more than 70; in 16 series (25%) he has averaged less than 35. Lara had a similar record of stellar series (11 in 35 series - 31%), but suffered relatively poor series slightly more often (11 again). Statistically speaking Lara had slightly more dips - which is probably just how you remember it.

"In Federer, tennis has produced one of the most complete examples of greatness. He brings together the artistry, grace and joie de vivre of the perfect amateur, and yet the relentlessness and durability of the ultimate pro"

Some bowlers are also justly remembered for their inspired peaks rather than unchanging steadiness. If I had to pick one bowler who, at his absolute best, looked pretty much unplayable, I'd advance the claim of Waqar Younis. When I was a teenager, the most devastating sight in international cricket was seeing two objects going in sharply different directions: the ball lethally swerving in at 90mph, the batsman involuntarily toppling over to towards the off side. If he was lucky, he'd merely be clean bowled. If he was unlucky, he'd hobble off with a broken foot (and lbw to his name). The numbers reflect those facts. Between October 1990 and December 1994, Waqar took 180 Test wickets at 17.

But intuitive judgments can be a poor guide to consistency. MS Dhoni's charisma and dazzling attacking skills suggest a volatile Test career. Far from it. Dhoni makes many more fifties than hundreds, and his average has been consistently in the high 30s. Among modern players Dhoni has the least volatile Test record of any batsman, with the single exception of the ultra-reliable Mark Richardson.

The challenge of measuring success inevitably adds to the complexity of assessing greatness. All sports suffer a version of the same difficulties. Bobby Jones Jr, playing as an amateur, won 62% of the national tournaments he entered. He was far more likely to win, statistically speaking, than Jack Nicklaus, who won 18 major tournaments and is widely regarded as the greatest ever.

Baseball offers a revealing dilemma. Babe Ruth revolutionised his sport as a spectacle. No one had ever hit a baseball with such joy and such power. But his overall batting average is only tenth on the all-time list, significantly behind the leader, Ty Cobb. (A further complication is that Ruth was a loveable character, whereas Cobb was a cheat, a thug and a racist.) Ruth's influence on his sport adds yet another dimension: greatness as an agent of change. Even if you prefer Verdi's music to Wagner's, you will have to concede that the German composer had a far greater influence on the history of music. How do you measure that?

The tennis ace Rod Laver won "only" 11 Grand Slams (Roger Federer has 17). But Laver's 11 included all four in two seasons*, something that only he has achieved. Some pundits rate Laver as the greatest because at his peak his dominance was more complete. And how should we weigh the relative greatness of Pete Sampras and Andre Agassi? Sampras won more slams and dominated their head-to-heads. But Agassi won each of the four slams, demonstrating greater versatility.

In Federer, tennis has produced one of the most complete examples of greatness. The striking thing about him is the combination of beauty and consistency. Federer brings together the artistry, grace and joie de vivre of the perfect amateur, and yet the relentlessness and durability of the ultimate pro. He is like David Gower and Don Bradman rolled into one.

Federer's greatness is both "high" and "broad". His play in 2006 and 2007 is often held up as the high-water mark of tennis. But most sportsmen who enjoy such total mastery tend to give up early. Bjorn Borg retired at 26, the Welsh flyhalf Barry John quit at 27, Bobby Jones Jr gave up elite golf at 28. As soon as the magic fades, they rush for the exit.

Not Federer. He was overtaken as No. 1 by first Rafael Nadal, then Novak Djokovic. But Federer reeled them both in, regaining his No. 1 spot (for a while) in 2012. Many tennis insiders rate Federer's resilience as a member of the chasing pack even more highly than his period of solo domination. Something similar can be said of Tendulkar. His consistency and longevity are at least as remarkable as his best purple patch.

The question of whether to judge a sportsman by the height of the tallest peak or the volume of the total achievement reveals our broader attitudes. Is sport essentially like business, getting the job done, winning a series of transactions, securing profit in the bank? Or is more like the arts (as I explored here)?

Ask a businessman whether he'd prefer one astonishing year and nine average ones, or ten very good years straight, and you know he'll choose the latter. But ask a concert pianist if he would rather leave behind one peerless recording or ten merely impressive ones, and you may well get the opposite response. Robert Frost claimed his utmost ambition was "to lodge a few poems where they will be hard to get rid of". He was right: quality, not quantity, is the surer guarantee of permanence.

Unable to forget the wristy majesty of his 281 against Australia, you may insist that VVS Laxman is a better player than his more consistent peers. Yes, they can blind you with numbers. But you have the right to judge sport on your own terms.