Here is a five minute bar chart today's e-mini day session. In the up trend from the 865 low there had been two previous breaks of about 15 points. A third break of that size from yesterday's high at 976.50 would have carried to the dotted green line you see on the chart. When the market is strong is tends to stop before it gets to an exact resistance level. So when the e-minis made new day session lows I got long at 963.00.
I was prepared to buy the second unit near the low of my range estimate for today of 960-75 (blue rectangle). Instead, the market rallied immediately. I sold my long unit after I saw what I thought would turn out to be a volume climax bar (red arrows).
I am generally a pretty aggressive profit taker. My aim as a trader is to take advantage of fluctuations around an underlying trend. But I get even more aggressive taking profits after an 8 day, uncorrected up trend such as the one that began from 865. I have found that people tend to place way to much emphasis on how they get in to a market position. It is my view that learning to accept profits at the right time (which will depend on the position of the market relative to its underlying trend) is of equal or greater importance.