For the ladies, it will be like: bare feet, socks, nylon knee highs or nylon tigh highs/pantyhose.
For me, the division is about 20% of the time bare feet, 20% with low "summer socks", and the rest with the type of sock you wear under a suit. Black or dark blue.
Reasons why always welcome: climate, comfort, obligation (for example uniform), need to wear protective gear for work,...
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