Why can DNA replication errors never be completely eliminated?

In the context of Darwinian medicine, DNA replication errors can never be completely eliminated because they are an unavoidable engineering constraint of biological systems.1

While cells possess sophisticated mechanisms to maintain the integrity of the genetic code, such as the "proofreading" ability of DNA polymerase and various DNA repair pathways, these systems are not perfect. Evolution does not produce flawless designs; rather, it shapes bodies through trade-offs where perfection is often impossible.2341

The persistence of these errors is a fundamental vulnerability of the human body. Because natural selection optimizes for reproductive success rather than absolute health or longevity, the biological cost of achieving error-free replication likely outweighs the benefits. Consequently, mutations resulting from replication accidents remain an inherent, inescapable aspect of life.15