A 15-year-old boy, hooning in a stolen BMW, being watched live by tens of thousands of people online, vanishes into air almost as thin as that between his ears.

You could be forgiven for thinking he was a budding Daniel Ricciardo​, the beneficiary of a bumbling police force, or maybe a bit of both.

But it's hardly that simple. The police decision to end Friday's pursuit of the boy as he approached Bendigo was taken with only one thing in mind: risk.

No doubt some of those watching were waiting for road spikes to be deployed, a wailing police car to fly from left of screen and T-bone the stolen car, or - as we have bizarrely witnessed twice before in Melbourne – a road block to be constructed from civilian vehicles.

Instead, as the boy careened towards Bendigo at speeds of up to 150km/h, appearing set to hoon into the bustling regional centre at one of the busiest times of day, the police and television helicopters peeled away, and the sirens faded into the distance.

It is difficult to gauge exactly how police assess the risks of these pursuits, as they claim one of the main advantages of the new policy, which was implemented in late July, is that crooks don't know anything about it.

Under the previous pursuits regime, it became known that there were only certain types of offences that warranted a pursuit. Before too long, doughnuts (no, not that kind) were being flaunted in front of police, U-turns were increasingly being done when drivers approached booze and drug buses, and, in two instances, police were unable to pursue stolen cars whose drivers then killed innocent people.

Police wanted the new policy to be more discreet, and give officers more discretion.

This means it is difficult to know exactly what the officers in charge on Friday weighed up before they decided to abandon their chase.

It is likely the age of the driver, the behaviour he had exhibited, the area he was about to enter, and perhaps information given to them by the two teenage girls who were passengers of the boy earlier in his wild ride before being arrested, all contributed to the decision.

They may well have turned their minds to other factors. Such as the 14 people who died in police pursuits between 2010 and last year. Or the more than a dozen serious incidents that have happened in the four months since the pursuits policy was changed, including an officer being jammed against a wall by a pursued car and having to shoot dead the driver, and at least seven instances of police cars being rammed.

Police Minister Lisa Neville said on Saturday that she wouldn't second-guess the decision to call off the pursuit.

Given nobody was killed or seriously injured, perhaps we shouldn't either.