There are several mistakes on home design, not suitable color choice, how to locate the right furniture on the right place, the function and the location of furniture etc, on above picture, its a big mistake to put much picture on your wall, its look an irreguler arangement of decoration.
How about above picture, a really-really bad room, don't locate too much or fully decoration or furniture, to avoid this, we can use several minimalist furniture.Yes, it looks that the room is good, but there a little mistake, never put a floating or a chair with roller over the rug, its a malfunction. The best way to avoid a mistake in home designing is read a lot of book about home design, and find out other best home design.