Government spending has repercussions on the economy, just as taxation does—and both the spending going out and the tax revenues coming in are to some extent beyond the existing administration’s control.
When production and employment go down in the economy, the ==tax revenues== collected from businesses and workers tend to go down as well.
Conversely, when production and employment are booming, more tax revenues come in and there are fewer individuals or enterprises receiving government financial help, so the government tends to be removing purchasing power from the economy at a time when there might otherwise be inflation.
The weighing of costs against benefits, which is part of the allocation of scarce resources which have alternative uses, can be greatly affected by government ==expenditures==.
While there are some goods and services which virtually everyone considers desirable, different people may consider them desirable to different degrees and are correspondingly willing to pay for them to different degrees.
Many government expenditure patterns that would be hard to explain in terms of the costs and benefits to the public are by no means irrational in terms of the ==incentives== and ==constraints== facing elected officials responsible for these patterns.
==Government budgets==, including both taxes and expenditures, are not records of what has already happened, they are plans or predictions about what is going to happen, but of course no one really knows what is going to happen, so everything depends on how projections about the future are made.