While this is different in other games it isn't neccesarily a bad thing, just different. Gameplay wise at least.

Performance wise it's a big deal. I came from GW2 here and there different tick times ment that they had to limit the number of dots a mob could have and even drasticaly limit the number of mobs you could hit (to 5) so you don't dot up to many things at the same time. Of course, 1 person dotting doesn't put much stress on the system even if dots up a 100 mobs. The issue is when the whole population of a server does it.

Honestly I wish they had the same sense of efficiency in other areas...