I think that those who have experience and skill in trading should never be afraid to trade, because they can make profit whenever they trade, if they can make a close estimate using previous experience, it is possible to make a good profit. If one is able to wing 7 out of 10 trades then he will be in profit.
Experienced traders are not afraid of risk or trade because they have the idea to cope up with the risk but newbies often feel insecure due to high risk in trading as they have not experienced it before.
If any person knows well about the market and the coins then he will boldly decide about his next step but those who don't know anything will be afraid that his decision may not turn into the wrong decision. If your losses are minimum and wins are maximum then you are a good trader but if the number of losses increases then it is necessary to take a break from trading.