BUSINESS LIFE:FOR 75 years, Jiro has been doing the same highly repetitive manual work. Since he was about 10, this 85-year-old man has spent most of his waking hours arranging little pieces of raw fish on to compressed balls of sticky rice. You might think he'd have got tired of it by now. But no: Jiro loves his job more than anything else in the world.

In Jiro Dreams of Sushi, David Gelb’s admiring documentary, we see the chef stare straight at the camera and say, with grim earnestness: “I feel ecstatic every day. When I make sushi, I feel victorious.”

The film, with its lascivious shots of raw fish, is all about the purity of work. We are meant to think that Jiro is weird but wonderful. He obsesses over every scrap of fish. He hates holidays and is only absent for funerals and emergencies. His sushi restaurant – in a grotty subway in Tokyo that seats only 10 along a thin counter – is perhaps the finest in the world and has won three Michelin stars.

Jiro is not interested in expanding: he cares only about perfection. “I’ll continue to climb until I reach the top, but no one knows where the top is,” he says.

To see someone strive so hard at something should be uplifting. But the more I watched, the more revolted I became.

At one point, he inspects a bucket of octopus and explains how he used to get his assistants to massage the tentacles for 30 minutes, but then found that if they did it for 20 minutes longer, the taste was better in some subtle way that I didn’t quite get. Watching this, I flipped. Such striving is completely mad.

Jiro – or anyone else batty enough to aim for perfection in their work –- isn’t a force for good. Such obsession comes with a dark underside.

In Jiro’s case, this is not hard to find: his childhood was of an extreme hard-knocks variety. The son of a bankrupt drunk, he was kicked out of home at the age of nine to make his own way in the world.

In turn, Jiro has forced his two sons to spend five decades in fish, setting them up for failure in a fight to compete with their sushi-mad dad. “There is nothing I can do to top him,” one says in a resigned sort of way, all fight knocked out of him.

Jiro himself is unbending. “You must dedicate your life to mastering your skill,” he says, eyes unblinking through round, rimless glasses.

I draw the opposite conclusion. You must under no account dedicate your entire life to mastering a skill – particularly if the end result is a mere mouthful of rice and fish. There are too many other interesting or pleasurable or worthwhile things to be doing instead.

I felt the same sense of repulsion and waste reading about Olympic gold medallist Victoria Pendleton.

Thanks to her recent venting in the Sunday Times, we now know that becoming the fastest woman cyclist in the world had a very dark side indeed. She describes herself as a skinny 15 year old trying to keep up with her cyclist father, tormenting herself with the thought: he doesn’t love me.

Her response to success when it came was darker still – to cut herself with a Swiss army knife.

Both in sushi and in cycling – and in almost every other area – we celebrate freakish success. We hand out gold medals and Michelin stars but blind ourselves to the madness that goes with such striving. A hunger for perfection in most things is grotesque, distorted and unbalanced.

Last week I was cycling through London – rather slowly, as it happens – with one of my own daughters in tow and we went past a building that said “Goodenough College” in large writing across the door. It turns out to be a residential hall for postgraduate students, named after a long-ago chairman of Barclays Bank.

At first I thought what an unfortunate name this was for an academic institution, but then, calling up the image of Jiro and Pendleton, I thought again. Goodenough College isn’t a bad name. It’s a good one. To be good enough is, well, good enough.

In most things, being good enough requires quite a lot of effort. More recently, chief executives of Barclays haven’t been nearly good enough. Nor have most other bankers, or most other workers, or most products, or, come to that, most newspaper columnists.

And most universities are nowhere near good enough either – they are increasingly places where students emerge with a lot of debt, having suffered more wear and tear on their livers than on their brains.

And as for sushi, at least in London, the day it becomes good enough really will be a day to celebrate.

At Eat, my local sandwich chain, the sushi is quite revolting. – (Copyright The Financial Times Limited 2012)