Mobs sometimes randomly stop attacking and following the target

Steps to Reproduce:

1.spawn a ravager, fox or wither skeleton
2.change your gamemode to survival or spawn a villager
3.sometimes the ravager, fox or wither skeleton will stop following and attacking the target for a couple seconds

Observed Results:

Sometimes ravagers, foxes and wither skeletons stop following the target for a couple seconds after that they will follow the target again

Expected Results:

Ravagers, foxes and wither skeletons should continue following the target until hes kill the target                            

Seems affecting almost/all mobs