Daily/every other day/longer. In my case it’s ‘longer’ . Much of it has to do with motivation but some is to do with not wanting to use the washing machine too frequently. I have been this way since a bout of akathisia/heightened anxiety where i was fixated/obsessed about the washing machine and not being able to get and plumb in a new one , to the point i was washing clothes in the bath. I have a ritual of using the washer when i have 2 dirty t shirts , trousers etc and a few socks/underwear. The longer i wear my clothes the longer between washes.
Something tells me this may be abnormal behaviour . A sign of illness maybe?