Unless I know I'm not going to have a chance to load soon, I usually keep less than 500 rounds loaded at any given time, and reload it in relatively small quantities as I shoot it.
I don't have the brass stash to load thousands at a time even if I wanted to, but I see a couple advantages anyway:
-If something goes wrong, I have less suspect ammo. I've never had a squib, but if I ever did, I'd only have up to 600 rounds or so at the most to be worried about. If I'd just finished loading 10k, well....
-If I ever want to change a load (like I do as the weather changes) it can basically be done as a rolling change without having to designate a large pile of ammo as the "old load, for practice only", etc.