Wool Socks should be kept and maintained in your main base and safehouses. They have the best decay rate of the socks (0.085%) allowing them to be stashed across the maps and revisited hundreds of days later without worrying about their condition too much. Example 100 day absence from your safehouse Wool Socks will only lose 8.5% condition. In comparision cotton socks would lose 66.5% condition. (Current game Decay Rates in Patch : 0.349) This is why you want to keep your spare clothes in decent quality or plan to visit a safehouse at some point to swap or repair them.