I read a very good analysis of why this happens with the judges: Dem senators will filibuster ANY real conservative judge should he/she get nominated, so almost all Republican nominees have to be cyphers-—stealth candidates who might, or might not, be conservative. That’s why our batting average is about 33%. But the GOP senators will never filibuster a lib judge, and they all are radicals. So their batting average is 1000. You cannot name one Dem judge, ever, who moved conservative after his nomination.
Byron White.