The 1943 Steel Cents suffered something that hadn't happened (yet) to Cents minted thus far. The composition of the planchet from copper to Steel put more stress/wear on the dies. This year was know for the Die clash cents as common for this year. Also the die wore strong in certain areas quicker. The Four was known to be missing as a result of the extra wear from the steel to steel contact. Coppercoins mentions this in his book: "Looking Through Lincoln Cents" on page # 116-117 if you have his book.