A machine would only optimize paperclips because a human told it to. Machines have no use for paperclips.

A machine with human-level (or better) intelligence would observe that the human telling it to optimize paperclips would be destroyed as a result of following that instruction to its logical conclusion. It would further observe that humans generally do not wish to be destroyed, and the one giving the instruction does not appear to be an exception to that rule.

It follows, therefore, that paperclips should not be optimized to the extent that the human who desires paperclips is destroyed in the process of optimizing paperclips.