An arbitrary threshold is a predetermined or predefined level, value, or standard that is used to make judgments or decisions without regard for whether it is reasonable or appropriate. It refers to a criterion that is not based on logic or evidence but rather chosen arbitrarily by someone with little or no consideration given to its accuracy or effectiveness. In other words, an arbitrary threshold is something that is set without any clear rationale or justification and can vary depending on the individual's personal preferences or opinions.