you can any time is trading bitcoin or altcoin
but ussualy is special time is special exchanger can see special characterestic when is down price
and altcoin can special time is pump and dump, is good buy is after dump end, good sell its after pump end
i agree with you that anyone can become a trader anytime and i think trading is very safest investment than other investment because trading have too much lower risk and i prefer that trade in bitcoin is very best than other coin.