A leftward shift of the supply curve due to increased production costs will always lead to higher prices and a reduction in quantity sold, regardless of demand changes.

When the supply curve shifts to the left because production costs go up, it means that producers can make fewer goods at the same price. This increase in costs might come from things like higher wages or more expensive materials, making it harder for sellers to supply the same quantity of goods. As a result, to cover these costs, sellers often raise their prices. For example, if a bakery faces higher flour prices, it might sell fewer loaves of bread at a higher price. So, even if the demand for bread stays the same, the higher costs mean less bread is sold, and prices go up.