Eth has increased more than 20 times during this year, litecoin 33.
Monero more than 40, and ripple more than 60.
Do you really think that if you invest in one of those you are going to be millionaire in sometime? You already missed the train
Be realistic about your chances and you will be fine. In the past we had altcoin rallies which gave 20x, 100x or even 1,000x returns in less than one year. But you can't expect them to repeat every now and then. Be patient and hope for the best. If you are lucky, then you may get 2x or 3x profits, and even that is much better than the returns which you can get from other assets.
Its true because it is estimated that almost of the investors knows cryptocurrency and how it works. I think volatility would decrease by next year.