Accent walls are rarely the right answer for a cohesive design.

They work great on TV when the camera is only getting the narrow shot...
...but in real life, you're not looking in one direction only - You're turning your head and walking in different directions and most often you're not seeing that accent wall.

Even worse are accent walls that have no connection to other elements in the room - in this room, the red wall is liked to the red upholstery in the chairs and even the red bowl on the kitchen counter. Imagine if the chair fabrics were plain beige and the bowl was white - The wall wouldn't relate to anything else in the scene and it would stick out like a sore thumb.