I'm sure not all traders will agree with me but some could possibly be on my side...
Here are the reasons why;
1. It is quite stressful - old traders will soon give up due to mental health problems
I disagree with you on some points. From my experience trading in a couple of years, having the right knowledge is important for trading. Many people think the risk is about losing money, but it's not just that. With the right knowledge, you can reduce some risks and improve quickly. The real risk is not taking the chance to learn from an experienced trader. Some people are hesitant to invest in learning because they're afraid of being scammed.
Having better knowledge about trading is what sustains traders and helps in managing all risk in trading. Trading is very risky and it is so unfortunate that people go into trading without any knowledge to trade to gain profit but it doesn't work that way in trading. If a trader have no knowledge about trading it is impossible to gain a better result in trading.
You should know that there are two types of traders who get tired of trading. One is the trader who has been doing things wrong for years and eventually gives up. The other is the successful trader who has mastered the market and gets tired because there's nothing new to challenge them, leading to his own retirement. There's a big difference between the two.
A trader who understands trading won't get tired of trading because there is no reason of getting trading. Despite it is impossible to do without lose in trading, their are traders who are still making profit in trading and also lose some amount that they can afford.