Mistakes can sometimes be inevitable especially if you are still new in trading. It’s a normal thing, and that will motivate you to change and improve your trading performance throughout the process of learning.
However, the bad thing is, if you are a lazy trader who still chose to rely to your friends and repeat doing the same mistake again and again, that is a sign that you aren’t supposed to be trading, otherwise your capital, be it money and time will only go into waste.
Not sometimes, I'm sure all traders experience the process. Losses in trading are inevitable, for beginners who need a lot of experience and must be willing to learn from every new experience gained from the trading process. If you don't continue to update your skills and solve the trading problems you experience, what happens is you fall into the same mistake. That can happen to traders who are lazy to learn.
Cases of traders following advice from friends still occur a lot. Especially beginners who see their friends who are quite successful with their trading. So, trust in friends' advice will increase. The bad thing is of course that trading ability will not improve. Even what happens is just continuing to depend.