Not everyone can afford to start trading with a decent amount. Especially for rookies just starting with trading it's important to not go big from the very beginning. You need to keep in mind that you'll make a lot mistakes at the beginning, and thus starting with low amounts is a must.
That is true. when you trade with bitcoin, you can start trading with very small amount of bankroll - which, I also recommend to starters like me. It is so hard to lose big money while you are still learning good trading crypto currencies. There are occasional pump and dump in cryptocurrency trading, and a rookie who buy at the top of the pump with high amount of bankroll, then he will be TKO.
In the Poloniex exchange, if you have 0.01 bitcoin, you can trade it with many other altcoins without problem.