After selling over 13 million consoles in less than a year, the Nintendo Switch is undeniably off to a hot start . Looking into the future, though, how long we can expect the Switch era to last before its inevitable successor comes along?

In an investor Q&A posted over the weekend, Nintendo seemed confident it can extend the Switch's relevance longer than the usual cycle for a game console. "Up until now the hardware lifecycle has trended at around five or six years," Nintendo's Co-representative Director and legendary Designer Shigeru Miyamoto said in the Q&A. "But it would be very interesting if we could prolong that life cycle, and I think you should be looking forward to that."

Miyamoto cited the Switch's portability and unique hardware features, as well as a strong pipeline of games and development talent, in explaining that expected longevity. But there's some evidence that the days of a five- or six-year console generation are already past for the entire market, not just the Switch.

If we measure console generations from their launch to the launch of their successors, the last major consoles to last five years or less were the original Xbox and Gamecube. Nintendo waited almost exactly six years between the launch of the Wii and the Wii U, but there was a seven-year span between the launch of the PS3 and PS4, and an eight-year span between the Xbox 360 and the Xbox One.

The expected lifespan for the current generation of consoles has already been thrown well out of whack by the mid-generation upgrades of the PS4 Pro and the Xbox One X, of course. That aside, though, a "five- or six-year" cycle would see full successors to the PS4 and Xbox One launch sometime this year or next—something very few industry watchers feel is likely.

Looking at the lifespans of portable consoles changes the calculus a little. It was about nine years before Nintendo upgraded the industry-dominating original Game Boy with the Game Boy Color's slight improvements, and two or three more before the Game Boy Advance came along. The Nintendo DS, 3DS, and PSP all had lives on the higher end of the scale, too, lasting between six and seven years on the market before their successors were rolled out.

Multi-Switch households?

Some might expect the Switch to have a shorter lifespan than normal because its relatively low-powered hardware will have trouble keeping up with the kinds of games that will be available on competing consoles. Switch owners have already shown a desire for even scaled-down ports of years-old games , though, and graphical expectations for a primarily portable system can be lower than otherwise.

Part of Nintendo's confidence in the Switch's extra longevity, it seems, comes from the idea that the system isn't generally limited to one sale per household. "Our ultimate ambition is for a Nintendo Switch to be owned not just by every family, but by every single person," Miyamoto said in the Q&A. Only then, he said, will consumers be able to "take for granted that everybody has a Nintendo Switch, then we can create new and very Nintendo genres of play, and Nintendo Switch can have a life apart from smart devices and other video game systems."

This isn't a new concept for Nintendo. Company president Tatsumi Kimishima has said multiple times in recent months that he expects many households to buy multiple Switch consoles for separate family members. Miyamoto had the same vision for the Nintendo DS back in 2009, telling the Economist that "instead of selling one unit per household as with the Wii, Nintendo wants to sell one DSi per family member."

Selling more than one console per household isn't a ridiculous idea for a successful portable console. The Nintendo DS sold 32 million units in Japan, a number that suggests many households had two or three units lying around. These days, too, it's not uncommon for every member of the household to have their own smartphone or tablet, though those general use devices have pretty distinct value propositions.

Right now, it's easy to see why Nintendo has over-the-top confidence in its new best-selling console. Whether the system can keep the public engaged well past 2022 or 2023, though, is another matter entirely.