I think you have something there.
On Wednesday, with a little help from Daddy, our 10yo went through her clothes and has a fairly large pile that will be taken to the Hospice Thrift Store tomorrow.
I guess we're doing something right, because at the moment she is in her room doing the same thing with toys.....
Last month we all went through our closets, had 4 bags of clothes for Good Will. Told my youngest (11) to clean his room gather up his clothes and put them in the laundry bag. A few days later while doing laundry I was puzzled why he had hardly any clothes. I asked him where he was putting them. He said you told me to put them in the bag. He obviously didn’t hear me say LAUNDRY bag and put MOST of his clothes, in the Good Will bag which was long gone.