Errors that occur during DNA replication lead to mutations, which represent permanent, heritable changes in genetic material. These errors can pass from parent cell to daughter cells and affect many generations of cells.
On the other hands, errors that occur during protein synthesis lead to formation of defected or non-functional protein. These errors cannot pass from one cell to another and affect only one cell, which requires that protein for its proper functioning.
Thus, 'it is more important to check errors during DNA replication that errors during protein synthesis.'
