Why did American's lose more interest in Nintendo with the SNES than they did with the N64?

[kupomogli]

The same could be sasid about Europe and Japan. The SNES lost 150k in Europe from the NES, but the N64 lost 2.61m from the SNES. Japan gained 130k from NES to SNES but only gained 30k from the SNES to N64.