слабое звено определяет устойчивость структуры, системы в целом("The press can resist the standard of the lowest common denominator, the rationalization that all news is fit to print that has appeared anywhere else" (Edward M. Kennedy).The most basic, least sophisticated level of taste, sensibility, or opinion among a group of people. mym0use)
наименьший общий знаменатель(the lowest common denominator the least attractive, least intelligent people or features in a situation: trashy TV programs that appeal to the lowest common denominator. Alexander Demidov)