Once a year. I rarely wear them so I don't need to buy them
How often do you find something that you don't know what its for but it looks like it could be important so you put it in a drawer with the hundred other pieces of junk you don't recognise or use?
when stuff becomes unwearable it goes. Probably yearly? My wardrobe lasts a little over week without doing laundry. If it gets to less a week, I’ll go thrifting.