The ability to solve complex problems is a sign of maturity, intelligence and, some would argue, what separates humans from other species. Difficult questions can engage perception, knowledge, problem solving, judgment, language and memory.
A fair bit of money is deducted from your pay, withheld as income tax. The aggregate of all that tax money is what is known as discretionary spending, the tax money that Congress can debate and decide how much to allocate to various government services and programs every year. It is truly complex.