Based on the volume trade per day, the price and the user itself. If many people keep trading and using that altcoin so we don't need to worry about that. That altcoin will survive for sure, i think not only litecoin and dogecoin that will survive but other altcoin too like Dash, LTC, Ethereum, NEM and many else.
Agree. Altcoins survival is limited to the amount of trading volume it has, and user interest to keep it going. When an altcoin cannot deliver constant development and innovation, it will stale and eventually die as people will switch out to a different coin which is being actively supported by its underlying development team and community.
Of course, many altcoins have managed to remain actively traded over the years like Litecoin and Dogecoin, making them survive as long as there is money flowing into them. Perhaps, the altcoins we see today as the most prominent ones on the market, may not be so within a couple of years from now.
One thing for sure is that altcoins are usually full of hype, and when that hype cycle is over, people will leave them behind to choose the newest ones in the market. Take a look at ZCash for example, which was overhyped within its early days since launch, but eventually fell down in value, as the hype period came to an end.
Therefore, it would be wise to buy and hold old altcoins like Litecoin, Dogecoin, and even Namecoin for the long term, as they have remained stable in community support for many years since their inception. Just my opinion
