JEE MAIN - Chemistry (2015 (Offline) - No. 20)

Higher order (>3) reactions are rare due to

increase in entropy and activation energy as more molecules are involved

shifting of equilibrium towards reactants due to elastic collisions

loss of active species on collision

low probability of simultaneous collision of all the reacting species

Reactions of higher order $$\left( { > 3} \right)$$ are very rate due to very less chances of many molecules to undergo effective collisions.