They are not built-in, but slimmer than regular because the boxes themselves are usually 24-27" deep but the doors stick beyond the counter so they can open without hitting the side panels. No counterdepth I've seen has built-in style hinges with outboard pivot centers that pull the doors "in " as they swing open.

I have observed that wood-panel units actually look less convincing than just a metal door skin, because they sit on top of the door surface, further emphasizing the protrusion and sticking out beyond the adjacent cabinets.

I chose this simple looking CD with thin, flat doors and a 'trim kit' to get the most built-in look I could achieve at half the price of built-in.

Counter Depth....The body of the unit is cabinet depth, then add the doors for the overall depth.

Full Depth..... the unit sticks out a long way past the cabinet depth up to 10" in some cases.

Built In / Integrated.....door front will be very close to been flush with the cabinets if not exactly flush.