“Even an agent that has an apparently very limited final goal, such as “to make 32 paperclips”, could pursue unlimited resource acquisition if there were no relevant cost to the agent of doing so. For example, even after an expected-utility-maximizing agent had built 32 paperclips, it could use some extra resources to verify that it had indeed successfully built 32 paperclips meeting all the specifications (and, if necessary, to take corrective action). After it had done so, it could run another batch of tests to make doubly sure that no mistake had been made. And then it could run another test, and another. The benefits of subsequent tests would be subject to steeply diminishing returns; however, so long as there were no alternative action with a higher expected utility, the agent would keep testing and re-testing (and keep acquiring more resources to enable these tests).”

— Nick Bostrom, The Superintelligent Will: Motivation and Instrumental Rationality in Advanced Artificial Agents (2012)