"Murderers, in general, are people who are consistent, people who are obsessed with one idea and nothing else"

This quote by Ugo Betti suggests that killers are people who are driven by a single concept and are consistent in their actions. They are concentrated on one objective and will do whatever it takes to achieve it. This could be translated as an alerting to be cautious of people who are extremely concentrated on one idea and hesitate to jeopardize or alter their views. It could likewise be viewed as a commentary on the power of fixation and how it can lead to extreme and harmful behavior. The quote suggests that killers are not always evil or harmful individuals, however rather people who are so consumed by one concept that they are willing to do whatever it requires to make it a truth. This might be a cautioning to be aware of people who are excessively focused on one concept and to be conscious of the prospective consequences of such an obsession.