Nintendo wanted to ship 5.5 Million Wii U systems by April 1st
Nintendo actually shipped 3.45 Million Wii U systems by April 1st
According to VGChartz, 3.3 Million Wii U systems have been sold by July 13th
The sheer definition of "failure" is something that has a lack of success. A failure is something that hasnt met expectations.
The Wii U, right now, is a failure by definition.