I main a warlock if I completely miss with my ranged melee I lose the charge. it's the same with the hunter throwing knife. And the Titan melee is way stronger and is available in every subclass!
Because Titans do not have a ranged melee. The only melee charge you lose as warlock is ball lightning. Every other melee you do not lose, just as with Titans not losing theirs because they arent ranged.