Sometimes, it is very important to have the focal plane align with the subject to emphasize the composition. If the subject and the overall image are identical in shape, color and size, the use of selective focus will be more effective.
E-510 with Zuiko Digital 14-54mm f2.8-3.5
54mm, f/3.5, 1/250s, ISO100, -0.3EV
In this image, I selected the three-leaves clusters to align to focal plane. And I selected a medium aperture value to capture enough depth of field to render the clusters in focus. The rest of the image was blurred.
The morning sunlight provided a nice angle for the leaves to reflect the rays that casted a lovely maze of highlights and shadows. Somehow, the leaves looked very lifelike and 3D-ish. Awesome.