There are jackets that come without matching pieces, that in fact should not be matched with the same fabric or sort: such as corderoy, jeans or leather. A corderoy suit turns you insteadly into Nerd the wanna-be professor, jeans suits are so very eighties and leather well hell's angel...
BUT most other jackets do look great when paired with their respective pants or skirt. And not quite so great, when worn with a mismatching piece. Of course we all need some mileage out of our wardrobe, but it is strange that royal ladies, that can afford to retire an outfit after two or three airings are so very against wearing a matching suit: I do like some of the jackets but the combo with the pants make them look boring.