Evaluation, monitoring, inspection and performance auditing have become a booming business. The numbers of professional societies have strongly increased and there are so many studies that authors recently referred to them as ‘streams’ and ‘fleets’. Evaluation has also been called a ‘positive social epidemic’. This article reveals that the booming business not only has positive consequences and ‘added value’, but also unwanted downsides. ‘evaluation machines’, ‘death by evaluation’, ‘evaluitis’ and the ‘performance paradox’ are examples.this article presents three possible explanations for the situation in which a booming business goes hand in hand with the beginnings of diminishing returns of evaluation for society. The first explanation is that evaluations are becoming part of management support systems that produce information that often only reinforces management decisions. The second looks into the unintended and negative consequences of ‘paradigm wars’. And the third suggestion deals with the limited explanatory power of evaluations.