One common mistake people make in trading is when they trade against the trend, most times they do this to hit a huge Profit but this is classified as gambling, there's no form of risk management involved in this. Trading involves taking strategic risks not careless ones. It's quite normal to have losses every now and then but when the be a constant occurrence it means that there's something you are doing wrong. Some beginner traders only care about making Profit without actually focusing on gaining knowledge first, you must learn before you earn that's how the financial market works.
Some people don’t really know how to trade they follow up chat share by others and the kind of trade others do it’s not something that they study to know the risk level involve, and that get them to losing every now and then and some still don’t care they just consider it to be a bad trade they which they can overcome with just one good win which is what usually keep pushing them to trade more and more.