If ever you wanted to know what could go wrong with paying people to dig holes in the ground and then fill them in, look no further than England’s coronavirus test and trace system.

The idea behind a crude Keynesian fiscal stimulus such as we’re seeing is that it does not matter much what government spends the public’s money on. That cash will end up as people’s income, which they will spend. It then becomes someone else’s income and multiplies the original public expenditure significantly to ease a nation itself out of a metaphorical economic hole.

The test, trace and isolate programme was introduced in England in May. It was expected to bring huge returns to the economy, with the Treasury allocating ￡12bn to it this year, comparable to what the government spends on nursery and university education. The promise made by Matt Hancock, health secretary, was that it “will help us keep this virus under control while carefully and safely lifting the lockdown nationally”.