EVerywhere what you mentioned there is risk involved but we have to move according to researches we made but the riskiest one is gambling which we cannot able to guess whether we are going to make money or not. For me, gambling is the riskiest one and for mining, we need a lot of investment to get profits.
You must eliminate gambling from your topic because it is not business nor a way of making money. It is totally loss. Anyway I like trading because with trading I can make big money in less time. But it needs experience and tactics. If I have the ability of affective trading no doubt I will become rich in the future. Wrong decisions can take you in debts.