Im investing small ammounts of bitcoin into some altcoins that i believe are under the real value, soo i will hold them till end the year atleast and then i will think what i will do if sell or wait a bit more, usually the savings returns good profits and almost without risk.
Well, i don't think holding altcoins is a good decision as we never know when the price grows and drops of altcoins, we can see that their prices are dropping and growing daily so it is good to trade them for short period but holding for too long can be risky i think.