Stun grenade, does it work?

I feel the stun grenade is inconsistent. I guess that’s practically everything in this game. Theres a lot of times were I just get a hit marker on someone and it doesnt stun them. It can practically be under or in front of them and it just wont stun. Getting head downed when they should be stunned is pretty annoying

Shock, flashbang or frag…