15% a day? Mate you are craazy, it is more than impossible and i am more than sure in that you are never goign to be achieving those numbers in less than 24 hours. Take inconsideration that we are still on a bear market, the volatility is more than high
in the altcoin market where there is at least a dozen pumps every day earning 15% profit per day is considered nothing! it is actually quite easy to do if you master the market and learn how to detect these pumps before it is too late and get on board to ride the manipulation partially to the top and make your profit.
whenever you are in doubt go to
https://coinmarketcap.com/all/views/all/ and sort the list based on 24 hour change and see the daily pumped coins.
I'm yet to see evidence of anyone ever averaging such high amounts per day. I think people easily get caught up in the good days and then overgeneralize those. Even if pumps are easy to judge eventually you'll get one wrong or the market will take an unexpected downturn when you have an open position and in such a volatile market you can lose a weeks worth of 15%'s in just one bad trade.