It sounds easy enough of application:
If you haven't worn it in a year, get rid of it.
Right. My first amendment was to increase the year to three. Time goes by so quickly these days. Three years is up before you know it.
My second amendment is the exception for expensive things. The reasoning should be self-evident, but I'll spell it out: I paid a LOT OF MONEY for this [or I would have paid a lot of money for this had I bought it, but I didn't because it was given to me or it was a deal but if I ever wanted to buy it it would cost BIG BUCKS] and I'm not just giving it away like that! Maybe I can find someone who will appreciate it. . . or sell it on Ebay? Hmmm. I'll have to think about that. Maybe I will wear it, after all. It was only that one time when I really was a little heavy that that dress made me look like a hippo in heat. But it's a Chanel, fer cryin' out loud! How bad could it look?! I'll wear it when I lose 10 more pounds.
While leads to three: I'm sure I'll weigh that weight again. One day.
Four follows function: you can't have too many basic black belts. Or little black dresses. Or simple flats. One more man-tailored shirt. . . I might need that coverup for the beach and there's a lot of wear left in those pants that were my favorites 5 years ago. For painting, maybe.
Five? Favorites. Enough said.
Six, sentiment. My mother gave me that skirt. It belonged to her mother. It's lace. Handmade. Nope, I don't think I've ever worn it. Look at that! There's no waist fastener. Maybe it's never been worn! How long have I had it? Well. . . . ah. . . .you see. . . . ten years? At least?
And I think I'll stop at seven, just because I'm getting depressed, realizing I could go on. . . and on. . . .
Seven is The Special Function I-might-need-that-one-day exception. Under this exception, I have a Bob Fosse beaded gown that I've never worn (see also exception 2, above), a Rennaisance festival cape and waist-cincher belt (hmmm that might look nice with the antique lace skirt. . . .), a vintage Irene suit, perfect for the film noir casting call, a student gown from Ireland, lawyer's wig, evil queen costume, thigh-high boots, Beduoin robe, and an assortment of black velvet formal wear. You can never have too much black velvet, as far as I'm concerned, and I see I've inadvertently strayed into Exception Eight: black velvet.