I don't consider myself to be a frequent shopper but in tracking my purchases this year, I discovered that I bought something every month. I was shocked because I recall thinking/feeling "wow, it's been a while since I bought something," when in realty, it wasn't the case at all!
To be fair though, I have used each and every item extensively and they are all favourites as I have been much more thoughtful in what I bring into my closet. Also, aside from some 'investment' pieces, I'm well under, what I think, is a very reasonable yearly amount to spend on my wardrobe.
So how long is a long time? Certainly 1 month is not long at all especially since none of my purchases were actual needs of necessities - wardrobe fillers, upgrades and wants, yes, but I can say that I could have gone without any of these purchases and still have a work-able wardrobe. (Not as stylish, but nonetheless, I would still be clothed).
I spent this year trying to really purge and perfect my closet, letting go a significant amount of 'dead weight' and really enhancing my wardrobe by just being more aware of what I was bringing in, and how it would work with everything else.
As an experiment, next year I challenge myself to only purchase something only when it is to replace an item that is used up and what I consider to be a wardrobe staple of mine. As a short term goal, I'm going to try to not purchase anything in the month of November - wish me luck! =)