Does anyone remember Ecu?Ecu was, Money of EU prior to Euro.Why was it a failure?It was a forced and theorotical money with almost no liberation for the EU members.
Well, there are many conceptual altcoins most of which are just therotically useful but no use at present and will just disappear and be forgotten in the near future.Some of the altcoins will pass the test of time and be used widely in future.ETH,XRP and/or a few.The total of crypto money will be less than 10.There may be digital coupons or discount digital cards etc but as a currency as a money the total number will be less than 10.

BTC will be the first survivor.Why because the founder cleverly dissappeared assuring he/she will not create a problem for the BTC.However, the other founders may have some genius,egocentric ideas for the currencies they developped.Because they believe the  currencies belong to them.

Founder who gives 2-3 percent per year to the app developpers and community will make his currency survive.