Tesco boss quits to spend more time with his family - but is there more to it?

The turnaround is complete, all the targets we set are being hit, my job here is done.

That, in summary, is how Dave Lewis explains why he has decided to stand down as chief executive of Tesco, a decision which has caused considerable shock.

Lewis arrived at Tesco five years ago on the back of several profit warning and falling sales.

He inherited a supermarket in a mess and a muddle and, within months, he was also having to deal with an accounting scandal when it emerged that, under his predecessor, Tesco had over-stated its profits.

Lewis arrived at Tesco five years ago on the back of several profit warning and falling sales. Credit: PA

Lewis’s approach was bold. He offloaded much of the overseas business and the UK brands he decided were “non-core” (remember Dobbies Garden Centre?)

The store estate was improved, ranges were overhauled, prices were cut and so too were jobs, in an effort to make savings.

Lewis organised the takeover of the food wholesaler Booker - steering the deal past the Competition and Markets Authority, to the astonishment of many - and launched the Jacks brand in an attempt to tackle on the Aldi and Lidl insurgency.

From the outside looking in, Lewis has done a remarkable job. Tesco share price may not have made much headway since 2014 but the business is demonstrably in better shape than it was back then.

Profits have risen, so too have sales and profits margins are plumper. Tesco is still locked in a bruising fight with the discounters but it is trading blows far more effectively than the other big supermarkets.

During Lewis's reign as Tesco chief, the company has cut certain jobs. Credit: PA

Lewis says running Tesco has proved “all-consuming” and he’s leaving to “take some proper time out” with his family. Is there more to it than that? There’s no reason to think so. This is a bolt from the blue but Tesco’s chairman, John Allan, speaks of sadness and regret.

The road ahead looks uneven, it will be down to Ken Murphy to negotiate the hurdles of Brexit and beyond when he replaces Lewis in nine months time.

Murphy is an outsider who has no obvious experience in groceries but has plenty of senior experience at Walgreens Boots. His salary of £1,350,000 per annum will be 8% higher than Lewis, who didn’t take a pay rise in the time he has spent as chief executive.

Lewis has clearly enjoyed his Tesco adventure. “This business never sleeps and the operational intensity is high,” he told reporters this morning. “I love that intensity, it’s quite addictive”.

He found leading the UK’s biggest retailer thrilling but Lewis always seemed less comfortable with the scrutiny that came with it, from journalists at least.

“Drastic Dave,” some called him but Lewis bristles at suggestions he’s simply a cost-cutter and was keen to point out this morning that when he joined Tesco, 222,000 people in the UK worked for the organisation. Today, despite the redundancies of recent years, that number is unchanged.

It may not be a leisurely goodbye. Lewis will still be in post on October 31st and may find himself having to deal with Tesco’s response to a "reasonable, worst case no deal” scenario.

Lewis says Tesco has a “detailed, comprehensive” contingency plan but isn’t minded to reveal much about it. The business is trying to stockpile enough “long-life shelf items” to last a couple of weeks, just in case there are delays at the border.

A scramble to deal with the disruption that no deal could cause, particularly in the run up to Christmas, would be a hell of a way to sign off. One of Lewis’s greatest challenges may lie ahead.