Well, for me, accessories make the outfit in terms of quality and polish, but clothing makes the outfit in terms of self-expression.
Cheapo accessories drag the whole outfit down with them, but cheaper clothes can usually be improved vastly by good accessories. (Jackets and coats are the exception, if they are of obviously lesser quality they can drag down an outfit.) In that sense, accessories play a more important role for me in looking well-dressed, especially shoes. So for work, I often turn to the trusty Mikimoto pearl necklace, Vivienne Westwood jacket, Chanel bag and Charles Jourdan heels which help pull any outfit together, which could be Zara pants and an AA tee.
That said, personally, I find that clothes help me express myself better than accessories, just because of my more eccentric personality. No accessory in the world could make a basic pantsuit reflect my true style, but with my favorite Zucca dress, I could happily go barefoot.
But shoes are crucial: it's either good shoes or no shoes. I have attended cocktail parties barefoot when I didnt have the right pair

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