When Dick first became Robin Alfred was really pissed at Bruce for letting a unprepared nine year old fight crime, so B-man gave him a pocket taser so Alfie would feel like he was safer (it didn't help) and Robin was just enchanted by that taser, he never went anywhere without it, never fought anyone without using it and just developed a passion for tasering people, so much so that when he grew up he couldn't let go of it, so he made escrima sticks WITH tasers so he could still use the love of his life while fighting crime as Nightwing.
The og taser is in display on the batcave as the first and most efficient weapon that a Robin ever had. Damian is very jealous of that title and still doesn't understand how he didn't surpass Dick with his cool swords, little does he know how much chaos and destruction a untrained nine year old with a taser can inflict in a city.