Waves and currents redistribute sediment along the coast as fast as the stream can deliver it. The Adriatic is a pretty sheltered sea. It's not that waves are so strong here, but the deposition by the stream is slow. A baymouth bar on the Michigan shore of Lake Michigan. The cut through the bar is artificial.
Beaches tend to develop gentle curves punctuated by sharp cusps.
Long Tail Point in Green Bay. Beach terraces exposed by uplift near Santa Barbara, California. A wave-cut platform in tilted sedimentary rocks near Santa Barbara, California. Uplifted beach terraces south of San Francisco, California. Breakwaters catch sand but also prevent it from replenishing the beach further downdrift.