This one depends on the trader as he has his own targets on this activity. Some have short-term goals to acquire the profit that they want, whereas, some are for long-term to gain as much as profit that they think of. However, there's no concrete answer on this as the profitability depends on the project involved and the entry/exit point of the trader.
If you are a highly-skilled trader, you can in fact earn much more and much quicker in a short-term trade than in the long-term one. It only sounds too good to be true, no wonder why not many have that kind of talent but what usually happens is either a short-term trader earns lesser but quicker or they go for long-term and earn much better but only longer, (just like you said there). I think that as a trader, it doesn't really matter if what project was that.
Risky or not, but as long as they already decided to go for the short-term, they will always follow it. The same goes if they choose long-term. What I know is that it was only those investors are the ones where their project/coin of choice matters the most. Say if it is risky, then they will just opt for the short term but if not, and what they own for example is Bitcoin, they will automatically go for the long-term.