From my experience, it is profitable. I prefer short term than long term though in some instances I am forced to hold when prices don't go my way. My technique is that when the current price of altcoin is below by 10% its average price, I buy and then when prices go back to its average value I sell. I don't mind making many 5% trades per day.
Base on my first experience in trading I also experience loss. Why? Because before I couldn't controlled my emotion. Im always kind a panic buying and panic selling every time I see that the bitcoin was falling im already selling my coin. And if I ever saw that bitcoin are moving up. Then Im going to buy immediately. And as a result I experience loss and regrets because of the wrong decision I've made.