Interesting replies - definitely a mixed bag! I have no issues with repeating outfits but I'm merely referring to posting the pics of a repeated outfit.
I certainly repeat many individual items (e.g. my black ponte knit sheath dress, my black pencil midi skirt) and post those pics because the outfit is different overall because there is a new element mixed in but I think (for me) I've decided NOT to post an outfit if it's being repeated in exactly the same way/in its entirety (clothing, shoes, handbag).
I understand that not everyone sees every outfit post and there will always be someone new who is seeing your outfit for the first time but there are also many members who have already seen that outfit. It doesn't mean I don't feel fab in that outfit and in fact, it may be one of my favourites, but I've already shown it.
Natalie - you make an interesting point about wondering if wanting to post new means you may be purchasing more. I guess that's something each person would need to resolve on their own.
And I gues the time between the outfits (as per Teri's point) makes a difference. If it's been quite a while since you wore it, that's one thing, but I wouldn't want to bore anyone with an exact duplicate of an outfit that I wore 2-3 weeks ago.