The Evolution of RNA Viruses

The outcome of the replication cycle of an RNA virus is that you have a low fidelity copying of genome. The outcome of human cells multiplying their genomes results in high fidelity, genome duplication. So why doesn't it evolve a higher fidelity replication strategy? And I would argue that the reason it does not is because mistakes allow you to explore new things. It's the same justification as to why I went to a liberal arts college, as opposed to a specialty school.