You are right, I have 7 or 8 'main' alt coins which I am trading with BTC and each one has a different strategy, usually when I spend enough time to form a strategy I'll eventually make profit. If I buy a coin without understanding it then the outcome is more random - it seems I have an equal chance of making a profit, loss or breaking even - but if its a loss then its high which disproportionately skews the profits.