Quote from gkramer:
I will gladly give up a little profit at the entry to avoid big losses incurred when using all in. I quickly know w/ my setups when a trade is going to work in my favor, and I can quickly add to my position.
Do you only scale into trades that go your way?
A trend-follower may want to join a trend on a pullback to the trend line, isn't sure exactly when price will pivot (slightly above, at, or below the TL), and so scales in 1/3 slightly above, 1/3 at, and 1/3 slightly below the TL, with a stop that fits his/her risk mgmt plan.
A counter-trend trader expecting at minimum a pullback from an oversold/overbought state with the possibility of catching a meaty reversal into a new trend may want to build into a full position starting at the oversold/overbought condition with contracts added even as price continues further (again with risk mgmt rules adhered to).
I watched an Oliver Velez live trading demonstration in which he scaled into a "loser" as it pulled back to the TL. On one trade he began taking profits as the trend resumed in the direction he expected. In another trade he felt the price action had weakened and he closed out the position for a small loss.
I found it odd that he was scaling in to a long position as price continued down rather than waiting for confirmation of support at or near the TL.
I'm more comfortable going "all in" to a confirmed setup rather than scaling into a either a winning or losing position in advance of actual confirmation, but I can also see the value in it.