Fences and walls can disappear with foliage used correctly but a gate at some point is seen up close and in detail. They are a wonderful place in any design to dictate architectural style. It makes perfect sense in many designs to have the gate act as an ornament and make its presence in the garden a focal point.
Hardware, hinges, and sandblasting wood may add a touch of age and distinction. Iron and wood are a time honored combination. Iron in itself has infinite combinations of ornamentation but lacks the privacy of a solid gate and may require a bit more maintenance.
Gates tucked neatly into a wall, enveloped by an arch or opening up to a view or focal point are design elements worthy of consideration in any garden.