For Nintendo Switch, I believe success will be measured extensively, as Nintendo themselves are hoping for a longer lifespan (longer than the average Nintendo console, home or handheld). As Nintendo Wii's sales plummeted very fast starting fiscal year '10, Switch could win slow and steady. 

It's a marathon, really.

I think it will need at least 80 Mil to be considering a success.

As the 3DS is near that

I have the impression this is a troll thread,but i'll answer anyway,since i have nothing better to do.

1- switch doesn't need to sell as much as wii u and 3ds combined to give nintendo profit, it's more expensive than the 3ds with games that cost more as well. Not to say 3ds was initially a bomb and wii u was a failure to the end. Also, switch still hasn't got to the second holiday season which can put it on par or above with the ps4,the console that rn is a success. Software sales are also stronger than ever, so i don't know what the concern with sales are here.

2- share drops happen all the time for a bunch of reasons, so if you want to use it as a metric for a company in general you have to look at it on an amount of time, not just a point. On march 3rd,when switch released,a share on nintendo was worth  around 21,000 yen ,now it's worth 41,000. I'd say we're fine in this front.

All the other points are either personal opinions like 3ds being a better portable(3ds never fitted in my pocket so i use the same bag to transport my switch as the one i used to carry my 3ds,not to say 3ds as a piece of hardware is awful imo) or lazily constructed(paid online is worth a discussion,but what you wrote is laughably simplistic and means nothing to the point you want to make.Sony is sucesseful now and have paid online, it's all about more profit.Nintendo would make online paid eventually even if they sold a 200 million more switches).

The one point i can give you is third parties not coming at large amounts, that can be improved. Still, we're having sucesseful cases of third party games there, so i wouldn't worry much about that. Tho it's true the better games are the nintendo games atm.

I believe switch will end up at around 90 million,nothing revolutionary,but a success overall. At this point in time however, looking at the price of the hardware and the amount of software sales, it's obviously a success if you just look at numbers for more than a minute.

Overall,i don't like most nintendo fans. They're loud and obnoxious and don't see past their little box with a logo. But i also hate trolls, so i thought i would try to debunk some bad critique i see on internet all the time.

I got your point, and yes, I smell a longer life cycle for the Switch, even though I would never place a bet :)  Things might change very fast without a significant notice, and for all Companies and consoles. I was not expecting Wii to slow down like it did from end of 2009, and 2010. Sony introduced Move, Microsoft Kinect, but that was really the reason behind the Wii progressive decline ? Perhaps partially, but I don't think it is to be attributed to the answers of Microsoft and Sony to Nintendo motion controller, being in my opinion the the most fun and versatile, my personal taste. Ok, PS3 got the cheaper slim, but still Wii had the best motion experience, and this is what made it so successful, selling like hot cakes for over 3 years.  What happened after? I could not predict Wii progressive decline, really.  So I will not try to predict anything about lifespan, as I still don't know what Sony and MS will pull out in Nov 2020(just a guess), and don't know how long Switch will continue to be so attractive. One very good point in favour of Nintendo is that they have no competition in the portable market, Nintendo is the king, and selling an Home Console together with a portable might sell very well for a loooong looong time.  Sure Switch is a success, and Nintendo is focusing on a longer life cycle.  

When I said about Wii being outstanding in the first 3 years, I was referring to raw selling numbers; Success in the long run is a different story, as you said, and Switch could be more successful than Wii, in the long run, as it appears its basic concept cannot be replicated by its competitors.

Exactly, Switch will fail without super-massive AAA games such as these, that's why it's selling worse than the Wii U, since the Wii U at least had COD.

I would describe the N64 as having been a "middling success" and the Switch will likely outsell the N64 in its first two years on the market.

With regards to last-gen, the 3DS did sell well but don't forget that Nintendo had to make huge price-cuts to kick start it and Nintendo also made almost no money on Wii U sales due to the outdated custom-tech in the gamepad. The Switch is a legitimate success because it had a strong launch and is sustaining strong sales a price-point that Nintendo can make money on.

I would describe the Switch as a definite and strong success. Maybe not as insane as the Wii was but I think that the Switch may have longer legs and stamina than the Wii.

There is punishment for short/1 word answers... but the only replies to this thread should all be a single word, has 3 letters in it, 1 vowel, 2 consonants, NOP. Especially given its failure to have outsold the ps4 already even though it's beating it so heavily in Japan that clearly means in the EU and US regions the switch has sold -60million units in the last 18 months, it really is a testament to how much the world hates Nintendo and wants them to go mobile/3rd party/free to play.

I mean... I think the world is still reeling from the weak E3 show... no live broadcast, no artsy lute concerts mid presentation and no gears of war, what were they thinking, it's WiiU all over again.

??? It had Twilight Princess and Windwaker, Melee, Fzero GX, Fire Emblem POR, Metroid Prime 1 + 2, Pikmin, Thousand Year Door, Double Dash, Luigis Mansion, 1080, Animal Crossing, Pokemon Colo/XD, Baten Kaitos, Custom Robo... It had AMAZING first party games.

PLUS it had good 3rd party like Soul Calibur, Rogue Squadron, Tales of Symphonia, RE4, Beyond Good and Evil, Timesplitters, Skies of Arcadia. It actually had RPGS and fighters, which N64 had like 5 of combined.

See most of those games were quite weak in my opinion. Twilight Princess, F-Zero GX, and Prime 1-2 were great, and Luigi's Mansion was decent, but the rest, meh.

I don't think i mentioned failure of any kind.

What i said still stands: it hasn't gotten those big titles, despite the huge success of the console and the fact that in terms of age demographics and userbase, it's very similar to XB1 and PS4.
Not even announcements are being made.

Kinda makes you think how sustainable this success will be in the long run, doesn't it?
What will happen the next time there's no selling concept, no return to greatness for Zelda and Mario to sell the next HW or fend off the incoming PS5 and XB2? Wouldn't it be better if Switch already had that kind of library and be seen as a real alternative to Sony and MS?

Not having those BIG games might not seem much now, but when the times comes, it surely will make a difference!