The Secret of black dress.

So, why is it normally being said that keep one black dress at least in you wardrobe ? why is it so necessary ?the one black thing from up to the bottom can go around with any thing .. More over with any other shade you want to mix and match it with. Any gown  or a short black dress is perfect and good to go if you cant find anything at the very right moment. Just put on some jewellery or some shrug.Whatever occasion it might be just put on some nice wedges and nice earings if its a late night party and for dates and more keep it low with a shrug of some pale colour and you are good to go!