Scalping...
It can give decent returns when trading futures, yes. But the trades are never satisfactory. One can't afford to have a backup of 15-20 lots. Can do it in equities by spreading the orders.
e.g. if I want to sell Union Bank and my chart tells me sell at 113 SL 115, I can spread sell orders between 112.5 and 114.5, maybe selling 500 qnty at 25 paisa intervals.
But in futures, I have to sell 3000 in one go, and wait for the price to go my way. If I sell at 112.5 and the price goes to 113.25, all my mind sees is a "loss" of 2200 Rupees. That's when one loses sight of all the trading strategies and panics.