This is purely based on my experience in kCBT3.
So to get a quest item, or a monster kill count to your quest; you need to be the one (or someone in your party) dealing the final blow; yes the final hit; to the monster. With the amount of channels (which is like 1~3 most of the time) and the cluster of people snatching monsters, it can be pretty hectic to even get your quests done.
Furthermore, if it’s a collection quest where you need to interact with an object (that only has 4 spawn points and requires you to get 8 of it); it’s even more of a pain to complete them when the respawn of these objects take tremendously long.
Now, this can simply be solved if people partied up; BUT - even when people do party; I’ve personally experienced a map where a few party of 5 people are just on the map snatching up every single monsters and/or quest objects. Still a big clusterfuck and a mess.
My solution to this is very simple. One - as long as you get a hit on the monster, you can technically get the quest item or kill count from it as long as it dies. Two - increase the number of spawn point for these quest items; and/or increase the rate they appear.