This is because light shades and details like ruffles, pleats, etc., make your already full rear and thighs look larger than normal.
The standard A-line pull-on skirt dominates most collections, but you'll also find more flared versions, straighter skirts, skirts with kick pleats or side-splits and wrap skirts.
Though not that daring in the style department, bandeau swimsuits do have elements of fashion flair, most notably in the form of pleats.
The bandeau swimwear here is mostly featured in one-piece styles with pleats at the waist.
Betsey Johnson - A designer known for ultra girly and flirty swimwear designs, you can also expect intricate details along with the pleats.