Yes gambling and trading are two completely different fields these have no comparison.
Gambling is based on luck and you will lost your money most of the time but on the other hand trading required knowledge and skills that makes it a great field to earn money through proper hard work.
Yes gambling and tradings are miles apart, but when a supposed trader sets off trading without good enough knowledge, skills and experience, then there is really no difference. Guess work is no trading and it is only by understanding the market that sustainable profits are made possible other than that, it is all waste of precious time and money.
In fact, in any activity in which the individual does things without due study and planning, the individual is gambling. In any event in life risks become higher when you do things without due care, mitigating such risks is important not only in investments, but in everything in life.