When a supply curve shifts bodily to the left, it conveys that, at each given price, producers now offer:

1. A leftward shift of the supply curve is a decrease in supply. 2. A decrease in supply means less is offered for sale at every price. 3. Hence at each given price the quantity offered is smaller. 4. A larger quantity would be a rightward shift, and 'nothing at all' overstates the case, so both are ruled out. _Source: ICAI BoS CA Foundation Paper 4 Business Economics, Ch 2 Unit III "Supply", p.4_