I used to "save" clothes for special occasions, and then I found that they either never got worn, or they weren't nearly as fab as I thought they were when I went to wear them.
O I don't save things anymore; I wear them. Of course, some clothes are more special than others, and some are occasion-specific (for example, no one would wear a cocktail dress to pick the kids up from school... unless it was a situation of really, really odd timing), but I do my best to actually wear things. It reminds me why I love them, and I feel better about the investment.
As others have mentioned, some things date and I always know there will be something new I love. I have very few things that are irreplaceable, and most of those are accessories, which I get far more wear from than most clothing anyway.