Don't take the growth for granted.. At least for the majority of the coins in the long term.
Correct, at the current time keeping traction for altcoins is a hard thing to manage. The ones that can stay around will gain on the long run.
It is a long race for altcoins and even we can't see them growing wild but their potentiality remains.
This is how the market plays for altcoins and it is sad that more investors are focusing almost on bitcoin rather than to choose altcoins.