Final answer:
A decrease in the supply of a good can be caused by factors like increased production costs due to government regulations, higher input costs, a reduction in suppliers, natural disasters, and negative technological changes.
Step-by-step explanation:
Several factors can lead to a decrease in the supply of a good, causing the supply curve to shift leftward. Government regulations, such as those requiring the installation of pollution-control technology, can increase production costs, resulting in a lower quantity supplied at each price point. Additionally, a decrease in supply could be the result of higher input costs, such as when prices for raw materials or labor increase. Supply can also fall due to a decrease in the number of suppliers in the market, often as a result of market exit or consolidation. Natural events such as disasters or unfavorable weather can reduce supply by affecting production capacity or damaging existing inventories. Finally, technological changes that negatively impact production efficiency can also reduce supply.