Is politics supposed to be about maximizing the government's money? We saw where that lead with businesses. I thought the government was there to do things that weren't good profit maximizers but made the world better.
A government is a collection of politicians. Those people are power seekers by definition. Almost always, the increasing the size of the budget under their control increases their power.
Politics is supposed to make maximizing money a good idea.
All things being equal (which they're not) it would be a bit odd to choose a policy that ends up being more expensive. Either money doesn't work as it should or it's a bad policy.
In this case the hidden costs of police and health is a lot higher than the hidden cost in what is effectively a purely administrative change.
In most western countries there are few state-run enterprises so there's little "government's money". There's taxpayer's money, and they care how it's spent.
They are saying that a good justification for a UBI would be if it maximized the value obtained with the spending. If $1 spent on basic income were demonstrated to improve society more than $1 of police spending, and so on.
It's of course harder to measure value to society than it is to measure profit, but it is reasonable to consider it when looking at policy proposals.