Literally every single piece of financial literature on the planet contradicts your statement. Why? Maybe because of the very definition of Volatility which is:

"Volatility is a statistical measure of the dispersion of returns for a given security or market index. Volatility can either be measured by using the standard deviation or variance between returns from that same security or market index. Commonly, the higher the volatility, the riskier the security."
http://www.investopedia.com/terms/v/volatility.asp

In other words bitcoin going up and down 10% is somewhat volatile whereas bitcoin rising 1300% in 2013-2014 is very volatile. Trading altcoins in very very volatile. Make sense?