“Politicians and diapers must be changed often, and for the same reason.”
“Politicians and diapers should be changed frequently, and for the same reason.”
“Politicians should be changed regularly, like diapers, and for the same reason.”
“Politicians and diapers have one thing in common. They should both be changed regularly, and for the same reason.”
“Minds, like diapers, need occasional changing.”
“Mother nature changes her looks for the same reason any woman changes her looks—to be noticed.”