In beginning we cnt really master trading directly since theres lot of things must to learn first and also experience would be a big factor and you are right as we trade in the long run we could able to master it on how we gonna adjust our trading pattern. Its really unpredictable but we could lessen the risk by trading smartly.
trading is unpredictable of course. but usually it cause loose for whom who do long term trading. like buy bitcoin and hold for months. it is not that much risky for day Traders and Immediate traders.. you can hold your coins for one two days (if you are a trader) but don't hold for long time other wise be ready for loose.
and being master is not easy. it need years to be a trader master..
one suggestion start with altcoin trading. if you are a newbie.. altcoin trading don't need huge investment.
holding for one or two days could be considered as long time because as you see some coin that having huge volume in 24 hours running so fast and within one day or two days you will probably missed so many event that actually you can get some profit out of it,though most of traders always watching their monitors lurking the price fullday