'Intensive wear' to help cull clothing
If I go through my annual or biannual closet riff and find I have something that still fits, doesn't need any repair or anything per se, and yet I haven't worn much, but when I try it on, I say, hey this is okay, pretty good, forgot I had that--whatever--and after all that I am not ready to part with it, then....
I try to start "intensive wear," in which I try to work in opportunities to wear the item as often as possible, make outfits with it and wear them. Church is always good for this (fashion-forgiving and many levels of dress are acceptable), also what might be casual Fridays for some people(or anytime you don't need your sure-fire power outfit), or dates with DH. Times when a girl has some room to make a big mistake, in case the items really ARE dogs and you just haven't realized it.
After doing this, I can get a better idea of, well it looks good but isn't comfortable, or it looks okay at home but somehow not alongside real people (the "dated" look comes out here), or nothing I have really matches (so decide whether to invest more in an outfit or pitch it), maybe it IS great and I just forgot. Or, it's okay but I just have 3 other things I would rather wear for similar occasions, so, out it can go.
This idea is not so different from the closet-culling and planning that's been discussed, but it's more of an action plan to get something back into circulation to force a decision, because sometimes it takes several wearings in different situations to identify what's right or wrong.
This doesn't apply to those few things that are for only rare occasions that you think may still come up (typically very dressy, sport or climate-specific, or theme/holiday). But it applies to the vast majority of my clothing, which can be "tried out" in several different situations. It also helps me figure out--because sometimes I need help here--no, this is not for the ladies' tea, but still great for...."