Why lump sales together and miss all the detail behind the numbers?
Gen 7:
+ PS3 massive drop from PS1/PS2 for Sony due to it's cost, and 360 putting up major competition in price, specs, and features.
+ 360 massive increase over original Xbox for same reason.
+ Wii massive increase over N64/GC due to never before seen hype and casual reach for a console. Unfortunately the hype for many was short lived.
+ PSP piracy and a few popular exclusives give it good legs.
+ DS beats iPhone to the punch with casual touch based games.
+ XB1 bad PR, loss of competitive edge in price, specs and features. Still retaining some good faith built from 360 but may decline due to competition.
+ Wii U unsuccessful to create hype or casual reach, weak preformance and features for fairly high price. Sales return to prior N64/GC trend.