While Tesco's march on the UK retail market may seem relentless, there is a host of factors that will eventually combine to halt the advance of the British supermarket leader.
But it won't be for a good while yet. Figures from research firm TNS last week showed that Tesco's market share topped 30 per cent for the first time in the 12 weeks to June 19, up from 27.9 per cent just a year ago.
This is just the latest milestone in a process that has seen chief executive Terry Leahy's company double its sales since 2000, topple J Sainsbury from the top slot in 1997 and move into areas as diverse as insurance and contact lenses.
Tesco argues that the 30.2 per cent market share figure is misleading in that it excludes other retailers that sell food such as Marks & Spencer and Boots. But this also applies to the competition, and on the TNS headline measure Tesco is now virtually twice as large - and growing - as Asda or Sainsbury. Inevitably,
there has been a backlash, and the company's treatment of suppliers, competitors, staff and the environment have all come under the microscope.
Campaign groups such as Friends of the Earth have lobbied strongly against the retail juggernaut, while the website tescopoly.org.uk has become home to myriad protesting voices. There is little sign such opposition is affecting sales, however, where Tesco's razor-sharp focus on price, product availability and convenience seems to be winning hands down.
"There are usually natural reactions to this type of expansion: consumers get a bit tired or the competition gets a bit better," said analyst Nick Bubb of brokers Evolution.
"Tesco has been lucky in that the competition has been in disarray. But they'll eventually get their act together."
There are signs that this is already happening. Sainsbury chief executive Justin King can note with some satisfaction that his company's market-share slide seems to have halted, as the traditionally mid-market player puts a greater emphasis on low prices and product availability.
And Asda, too, backed by the mighty Wal-Mart and its huge buying operation, is not going to sit back and watch Tesco eat its lunch. New chief executive Andy Bond has already promised as much, pledging renewed vigour in its price-cutting. Tesco frequently points out that over 90 per cent of Britons have access to at least three supermarkets, and the degree of choice that has worked so well to Tesco's advantage is likely to prove a limiting factor in time.
Customers who have transferred to Tesco over the past decade will not be slow to go elsewhere if the perception that Tesco is simply too big gains hold - not so much in a sense of fair play, more as a result of the dislike of being pigeonholed.
"What we need in this country is a truly competitive market place. If you can achieve this, market forces produce the best possible outcome expressed as consumer interest," said Richard Hyman, analyst at retail consultants Verdict.
"Customers do want choice, and within that, an increasing number have chosen. There's plenty of room in this market for other players to prosper, and we need them to prosper."
There is little prospect of the regulators moving in to try and limit Tesco's growth. You cannot legislate against success, and the Competition Commission would only react if Tesco were to attempt major acquisitions, which it does not need to do.
Local planners may have their say over new out-of-town hypermarkets, but there is still plenty of room for Tesco to expand its other formats, such as the Express and Metro convenience stores and its Tesco.com website.
The single factor most likely to bring the growth in market share to a halt - however long it may take - will be whether Tesco can make more money elsewhere.
Getting value for money is a concept understood not least by Tesco shareholders, who, while enjoying group's current success, do not see UK expansion as an end in itself.
While Tesco's UK sames-tore growth is still comfortably beating the competition at around 6.8 per cent excluding fuel, international operations are expanding much faster.
Sales in Ireland, central Europe and Asia increased by almost 20 per cent at constant exchange rates last year, and non-UK sales are taking a steadily increasing slice of the £37 billion group sales pie.
But Mr Hyman said there was some way to go yet. "I don't think we're going to see Tesco hitting maturity in the UK for some time. The battle may ebb and flow but one thing that doesn't change is Tesco. In food, there's further to go, in non-food, much further to go."
