The study looked at what influences how governments spend money and how predictable or unpredictable their spending is. They used data from many countries between 1990 and 2012. They found that factors like how much debt a country has, how the economy is doing, and certain financial and demographic factors all affect how governments make spending decisions. Countries with higher debt tend to have more unpredictable spending, while having clear rules and good institutions can make spending more stable over time.