You are reading too much into it.
If I remove them too fast I get "where did that go?" emails, if I leave it showing "out of stock" I get "are we getting more of this in"... can't win!
If it shows out of stock expect it to mean it's gone till next season or forever if we can't get it again next time. Sometimes it will mean we have more in the pallet rack and don't have it in cotton yet which will happen at some point in the near future, sometimes it might mean I have more on the water and awaiting it's arrival.
Clear as mud?
The only sure bet is if it shows stock you can buy it, if it shows sold out you can't.