I'm not knowledgeable yet about in trading, but everything in trading was started all to basic stage of learning.
Aside from that, in this industry for you to become a trader you must be prepare and know what tools you are going to use
if your in the actual form of trading.
Being prepared is one of the things that a starter need to remember because if the person that want to become trader is didn't prepared very well then his trading performance will be not that good and more often lead to loss of trades and money. Anytime is the best time to become trader but it always depend on the person preparedness.
I agree, it depends on the person itself, the best time to be a trader is when you feel that you are ready and prepared to enter the world of trading. that means you are willing to learn more about it and ready to invest your money whatever the outcome and even its risky. as a newbie its fine to make mistake because from that mistakes you will learn how to be a good trader.