In short I would say this about last gen, from my point of view.
The Wii was extremely successful and rode on the hype for many years until it died out and Nintendo naturally moved on, with a lot of profit earned. Enough said.
Extremely successful. Money, money, money!
The Xbox 360 was very successful, had a one years head start that got them all the third party support early on which Sony had to fight hard to get back. It cost MS a lot of money but in the end I would say the X360 was indeed successful. Successful but not profitable. They got the market share they wanted but it cost them way too much to do so. Especially the money wasted in the Japanese market to gain absolutely nothing, I can only imagine how much money they invested in exclusive Japanese titles and advertisement, all for nothing. And all the money spent on the North American market, which indeed paid off at least.
Successful but... too much $$$/¥¥¥ needed to achieve it!
The PS3 had a horrible start and I would say that I can not call the PS3 neither a success nor a failure. They outsold the X360, even with a year less on the market, but it cost them a truck load of money to do so. So I would say that they were semi-successful at a very costly price. It cost them so much money the first years to turn everything around, in all markets. Sold their consoles at a high loss everywhere and had to do many changes until they finally could turn it around. And to win back all the third party support from X360 took them quite a while since it was the main third party console for almost the whole generation, in my mind. At least the first few years, the most important years. And not to mention all the market share they lost, some to X360 but mostly to the Wii.
Semi-successful but... way too much $$$/€€€/£££/¥¥¥ needed to achieve it!








