IOW pairs of sayings, each of which in its own sureness of the truth contradicts the other. 1) a) He who hesitate is lost. b) Look before you leap. 2) a) The definition of insanity is doing the same thing over and over and expecting different results. b) Practice makes perfect. Your examples?
Too many cooks spoil the broth. BUT Many hands make light work. A bird in the hand is worth two in the bush. BUT Nothing ventured, nothing gained. There are heaps like these.