I weigh and sort my brass and anneal every other or every 3rd loading for mid-range loads
For extended LR loads I anneal after every firing... the difference it makes on shot-to-shot consistency at longer ranges where minor variations will show up.
The consistency is easy to see and feel during seating step.
When done correctly annealing restores brass to it's ideal state for the most consistent loads.
The important factor is to be as consistent as possible during each step of the loading process.
