Each and every pair of socks is mated for life and wear-leveling is only a problem to the extent that I favor my dominant foot.
The clips have a high retention rate such that no more than one clip comes loose each wash cycle, which means it is obvious which socks made the failed escape attempt.
This hasn't been a real problem for me. I'm not sure why. Some of it may be that I buy black socks, not white, and some of it may be that I mix freshly laundered socks into the clean sock collection, so every sock gets used about the same amount overall.
You get one box per type.
Then you stuff the 50 identical socks into the same box. Replenish when at 50% capacity.