The way Japanese car makers stunned America's big three after the 'oil shock' of the 1970s remains a fascinating story. The secret of Japanese competitiveness lay as much in their fuel-efficiency as their process management techniques-better cars at lower prices, run after production run. Detroit car-makers went nuts ripping up the same Toyota model to reveal minor improvements-two bolts instead of four here, a fused plate there-in every successive batch. What they couldn't see: the operational costs furiously being crushed by Toyota's Just In Time (JIT) systems for lean manufacturing, as instituted by the legendary efficiency driver, Taiichi Ohno.

What Ohno sought was "the right part in the right place at the right time". Nothing should be idle. Not tools, not materials, not workers. Therefore, no inventory (a huge cost in sloppy systems) anywhere along the supply chain, to the extent possible.

Sure, it's easier visualised than done. It requires production planning to the minutest detail. Replenishment signalling systems ('kanban cards', originally, computer signals now) have to be superb, defective parts negligible, lot sizes standardised and labour flexible-for input queues to reduce to nothing, and every little nut to reach its appointed destination precisely when needed (or else, since capital costs money by the second, waste a few cents).

The benefits? Lower costs, yes, as mentioned above. The other edge, though, is the lead-time it grants over rivals when it comes to re-adapting the production line-up to rapidly changing market demand. A light assembly line can switch output faster and cheaper than a burdened line.

All it takes is management programming. Visitors to Japan used to marvel at the discipline of their workers humming away in perfect orchestration. But American technology, since, has blunted that edge. Computer networks allow real-time work coordination, and radio frequency identification (RFID) microchips are now used extensively to track every little object from foundry to factory floor and beyond. Most of the world's factories have taken to some form of JIT or the other, and JIT books are no longer hotsellers. But the fact still is that nobody's anywhere close to perfection. Look around. You'll see somebody or something idle.