there will nobody can easily predict the market value. therefore, regardless of the truth, some coins even bitcoins are in down price on first half years, and it will be up on the last of the year. it almost happens every year.
Every time has a moment and everything has a place. If this is not the year of altcoin you've been holding maybe somehow it would be. But not all are going down because this is normal.
Every coins has potential for growth as all investors wish for their coins for a higher price but not all coins will cross above our expectations. We don't know what is ahead and we are just doing speculation to give our self assurance that everything is good in the future.