Agreed with most of the things stated in the OP but IMO, being too hasty and lacking knowledge is mainly the trader's fault and could not consider a mistake in terms of trading and this actually pertain to new investors.
Even if people in the forum can read these tips, they will still do it eventually, one way or the other until they experienced it first hand and learn it the hard way. There may be some that will take a point of this and will apply to their trading decisions tho.
and how do you think can affect a large number of open exchanges on the pricing of coins themselves crypto currency? To date, there is a lot of project, but the market is still down there.
The market is still down where? The main stuff is how people tend to screw themselves in trading just because they are always in a haste to make profit without learning and that usually end up putting them on the wrong spot most of the time as they end up losing a lot. Speem28 got it right because no matter how big the market is and low, as long as you are knowledgeable as a trader, you will always have a very good chance to utilize the movements to your favor which is the actual benefits of trading a coin but a noob will never get.
Many mistakes may happen when we are facing sudden fluctuations of markets but when we are having proper plans to handle them quickly then we need to worry about negative market. Stop-loss must be one that kind. Moreover stop-loss is a plan but most traders are still missing it out.
Crypto trading has evolved abruptly, it's non-stop, and rapidly changing process. Mistakes arise due to lack of knowledge, awareness, and impulsiveness. Some mistakes in trading coins are chasing pumps, it's buying coins when it is at its peak, not thinking that the increase in price is accompanied by some pullback, so it's better to check trading volume. In addition, not knowing your investment, devoting yourself to doing research on which you plan to invest is a much, knowing the stability of the project, the team, and the advisors. Never be afraid to fail, it's the best way to learn something new and to develop your knowledge, it helps to decrease the risks and downsize the mistakes.