The problem is that if you could magically remove all the waste in the economy, but didn't find new work for people to do, then all that happens is you have a lot of people out of work, which is in itself a waste. The way our economy is built, the waste from people being idle is in many ways worse than the waste from people doing things that don't need to be done, which is why politicians are always pro-jobs and never mind whether the work is worth doing.

Leaving aside money, efficiency should never be a problem because there is always plenty of work that urgently needs doing. Freeing up people to work on more important things should always be a win.

That's not the world we live in. To explain why, you need money: nobody will pay for it!

Convincing people to spend money on things that urgently need doing is the heart of the problem. The broken window doesn't have that problem. It's a waste, but it's a very convincing reason to spend money, and the shopkeeper has money, so that's what happens.

Building a new building could be a waste, too. Overinvestment happens and new buildings do stand idle sometimes for lack of tenants.