The most important is that when it comes to reproduction human beings will prefer sex with another to spending a few hours and tens of thousands of dollars at a fertility clinic. If the choice is sex or a Petri dish bet on sex. Those who favor allowing human cloning or who want to promote it argue that cloning may still help some people. Human cloning can be used to bring back deceased loved ones, to allow some of us to achieve immortality or to solve the chronic shortage of vital organs that results in so many otherwise preventable deaths. Cloning can do none of these things.
Cloning can no more bring back the dead than can owning a videotape of a deceased person.
Genes do not control our minds and our thoughts. Clones are people made in an unusual manner. Replicating a person's genes does not replicate the environment and the developmental that make the person who they are. It is simply impossible to step in the gene pool twice. Evidence that having the same genes does not make us the same person is all around us.