There are lots of common misconceptions about annealing that are so common because no one who knows ever explains it in a detailed enough manner and those who do are not metallurgist that can back it up with undebatable proof. Which does not exist on internet forums.
There are a few things most will agree upon.
Consistent and regular annealing will yeild consitent case necks that provide consistent properties and result in more consistent shot to shot accuracy. If you cant do this sometimes annealing less often or not at all may be a better option.
Quenching does not affect the hardness of non ferrous alloys.
Use caution to not anneal the area around or including the head. This is bad!
Most reloaders are seeking a restorative anneal, ie trying to return the brass to the condition it was in before firing. By annealing at a temperature to high you can fully anneal brass returning it to the softest state it is capable of being in. This can also be done by increasing the duration of a givin heat.
As heat increases the duration of time it takes to anneal becomes shorter.
Brass can be hardened by working it, ie work hardening. The greater the work the faster it hardends.
All brands vary in dimensions and composition, and one cannot assume they will respond the same to the same annealing process.
Manufactures use work hardening and annealing to control what parts of the case are hard, which are soft, and to what degree.
