The thing about kill stealing ...
Late game- it's just war, kill who you can and push. But early on when kills help a lot it's important to leave the kills to your carry roles. The only time I EVER care about KS is when the support just doesn't stop attacking the enemy even though there is clearly no way of him escaping. Or when there's like one enemy and three of you and your Braum decides to bop him with a Q when they are about to die. Just stop attacking! If you're the support it hurts your team more than you think to take early kills. Especially for junglers who have to use their time carefully. Did I just really spend all that time bot lane for thresh to get a double kill? Pls supports, just evaluate the situation