In the United States, a failure to pass a budget for the new fiscal year results in a government shutdown, during which all government agencies lose funding except those which are funded through other avenues (for instance, the Postal Service, which funds itself through the sale of stamps), and all employees of now-non-funded government agencies (except for those very few whose work is considered essential, such as air traffic controllers) are temporarily laid off.
Why not make it so that, if a budget can't be passed by the time the new fiscal year starts, funding simply continues at the same levels as the previous year until such time as a new budget can be passed?