Because it was just too weird.
The Japanese have long been known for having interesting taste in cars, notably small ones. They're called Kei cars, and they include everything from small passenger cars to micro vans and tiny pickup trucks. Japanese automakers are fully aware this niche won't work anywhere else but Japan, but at one point they figured it was worth trying similarly styled cars in the US. A somewhat successful effort was the Honda Element. A borderline disaster and now laughing stock effort was the Nissan Cube.
Unveiled to the US public in 2008, the Cube went on sale the following year. Despite its fairly sizeable interior and several other convenience features, its exterior design was just too strange for even those who go out of their way to be trendy. Power came from a 1.8-liter four-cylinder producing just 122 horsepower and 127 lb-ft of torque. Most (and there weren't many) Americans who bought one opted for the optional CVT instead of a manual. Aside from its general cube design, it featured even stranger looking rounded and curved styling cues front and rear as well as the side windows. The bottom line here is that Nissan's attempt to try something different with a five-door hatch in the US market simply didn't work. Can't blame them for trying.
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