Pyramiding scales into strength. A classic pattern is 4 units at entry, 3 more at +1R, 2 more at +2R, 1 more at +3R, with the stop moved up each time so the combined open-trade-risk never exceeds the original plan.
Done properly it raises average size only on trades that are already working, which is where the fat right tail of most trend systems lives. Done badly it is just late buying: each add worsens the average entry, and a retrace that would have been a small winner becomes a loser because the full stack is stopped together.
Two rules keep it honest. Each add must be smaller than the last, and after each add the worst case from here - not from entry - must stay inside the limit. If a pullback to the new stop would turn a +2R open gain into a loss, the pyramid is too heavy.
Related: scaling-in, anti-martingale, open-trade-risk