Very good marketing creating a lot of hype prior to launch combined by Breath of the Wild being available at launch, followed by a decent stream of high quality games during the following months. Compared to how the Wii U was marketed for example, Nintendo did a much better job in conveying what the Switch is like to people.

Tons of reasons. Ask Rol, he has a nice thread.
Mostly, I would say it's on marketing + the fantastic year 1 lineup, and 3DS + all 4 Wii U owners being ready and excited to upgrade for a while now. That's one of the reasons I think the PS4 was so succesful early on. The great support of a predecessor gives confidence and hype for next gen. That only applies to 3DS for the Switch, but how many Wii U owners didn't have a 3DS?

Its a real break from the tedium of PS4 and X1 that's for sure.


+As powerful as those devices are, they're not as convenient to use as Switch.
+As great as the libraries are of PS4/X1, there's a kind of majesty Nintendo's 1st party lineup has that's pretty much missing from competitors. The exclusive lineup this year is absolutely guns-blazing
+Better marketing and messaging all around made even more positive by outperforming optimistic predictions of the system
+I think there's a large community of gamers that liked the WiiU's games, but held off for this system

Cause Nvidia made great hardware that is easy to work with and Nintendo has lots of games that people want within the first year as well as the execution and marketing went as well as it could.

Because it's a great console and has an amazing first hear

Any more questions?

1. Nintendo.
2. It's actually a decent idea for a system, even if I personally find it's power lacking.
3. Games.

Definitely. The machine looks so good in the advertisements. Now people tell me "oh, you have the Switch! Can I play it?" instead of the "why do you have that Fisher Price toy over there?" when referring to the Wii U, which not even my little cousins wanted to touch. 

But as many have pointed out, its concept is also good and it's got the correct games. 

As of right now, it is doing fine. However, I would not celebrate it as a great success yet. It'll undoubtly outsell the Wii U. But beyond that, I'm not confident in it until I've seen 2yrs of sales

It has had a successful launch and I would love to see it be a long term success (especially since I just bought a second one ... I think ... damn Walmart) but it is still early, Sales could fall off a cliff after 20M units. Now I don't think that is likely but a fair percentage of their big guns have already been played. That said they do still have a potential silver bullet with a Pokemon.

Speaking of big guns I would love to see Nintendo break away from their model of 1 iteration of each title per console generation. I'd like to see them move to two per generation, I'd like to get another new Zelda on the switch as well as others. I don NOT want to see yearly releases though. I'd like to see what Nintendo can do with their own hardware at the start of the gen vs the end of the gen.

Living life like a pessimist isn't fun  

Just get crazy and wild!