I can sum up the mistakes better:
1. Nintendo's retro cartridge-based N64 - while CDs were already out and plenty. 16 MB typiacl storage capacity, compared to the CD's 650 MB.
2. Nintendo's self-imposed monopoly on cartridge-manufacturing on its Nintendo 64. Not only is it not CD-based, but the developers also have to buy the cartridges for $10 each from Nitnendo, who makes them. Nintendo cost itself the market there. Playstation - CD-based, $1 each, no monopoly on CD manufacturing.
3. Microsoft's incredibly costly entry into the console market in 2001. Billions invested without even establishing a market. $1.5 billion or so on an internet framework.
4. Sega's Saturn monstrosity. $400, several CPUs and GPUs.
5. Lack of game development for Gamecube and now Wii U, caused by lack of financial investment in software development by Nintendo.
6. Xbox 360 - another console by Microsoft despite overwhelming financial losses on their first. And reality law-breaking influence to make it succeed.
7. Wii U - extremely outdated, very costy. $365.94 - that's a lot of money for a system with a vastly outdated architecture. 12.4 GB/s system memory, 300 GFLOPS GPU. 300 GFLOPS is only slightly better then Xbox 360.
8. Playstation 3's Blu-Ray. Very costly at $100, doesn't improve the visual quality of the game. It could've cost $400 at launch instead of $500, and looked identical.
9. Playstation 4's Blu-Ray. Very costly at $50, doesn't improve the visual quality of the game. High-density DVD is enough, and would probably be $40 cheaper.
10. Playstation 4's 8 CPUs. Very hard to use. 2 CPUs is enough, and would cost 1/4 the price - $15 instead of say $60.
11. Playstation 4's 8 GB RAM. Would take 10 minutes to load that much data. 2 GB is enough, and would cost 1/4 the price, say $15 instead of $60.00.
Thus Playstation 4 could easily be $125.00 cheaper, and have games which look identical. Say $275.00 instead of $400.00.