The difference is that you call third party efforts bad, period, while the issue runs deeper than that. A big reason why Nintendo software sells is that Nintendo has built trust for three decades. Just like any other products in life, people keep buying what they know is good; and as long as it stays good, this won't change. The reason why third parties are running into problems is because they have built brandnames that stand for (vastly) inferior products on Nintendo hardware (especially on the Wii). They have released one piece of rubbish after another, so when they release a good product for once, there's a good chance that it will be ignored, because that's what people have been conditioned to do.
There's still some truth to your argument, because it doesn't bode well for games like CoD and AC when they require patches due to serious issues. That stuff won't fly on Nintendo hardware as easily as it does on other platforms, because people are used to properly functioning and polished games due to the standards set by Nintendo software (whereas on other platforms it isn't uncommon for first party software to receive patches).
I take issue with your comment that NSMBU is a cash-in, because its sales and reception don't support your assertion. It's about the only game (minus the majorly bundled Nintendo Land) that keeps selling and thus the only real reason to own a Wii U. The game's sales would be higher, but the problem is the console. It's expensive for the little amount of software it has. People don't really trust third party brands, so games like CoD and AC do nothing to persuade potential buyers. Many fans of Nintendo software choose to wait until more Nintendo games arrive to justify the purchase of the system. NSMBU will be bought once people get the system, but the first batch of third party software won't.
I knew you would take issue with my comment on NSMBU, I believe we had a discussion about 2d Mario's already, but I will come back to that.
I never called 3rd party efforts bad period, I worded my OP very carefully, my first since sentence was "To put it simply most 3rd party games are just plain terribly made or just cash grabs from publishers" that "most" isn't there by accident (yes I know that wasn't the first sentence). But I do believe games like COD, Assassins Creed,Fifa etc are cash grabs from their publishers across any platform they appear on.
I agree with your second paragraph those won't fly on a nintendo system.
Yes I think NSMBU is a cash-in by nintendo. Nintendo believed that since it was a high seller on the wii ,and it is probably easier to develop than most other nintendo franchise, that they could have released it as a launch title for wiiU and people would have bought a wiiU immediately because of it, that's not to say that it isn't a quality title. But as you said yourself most fans are waiting for more nintendo games to come before they buy the system because NSMBU is not a system seller to most N fans by your own admission.
Myself falls into this same category I will not buy a wiiU because of NSMBU, but if nintendo does convince me to get a wiiU I will probably buy it later on.
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