When a level breaks, it often flips role: broken resistance can become new support, and broken support can become new resistance. The retest is when price returns to that broken level to test it from the other side — one of the highest-quality entries in price action.

Why levels flip
The flip happens because of order flow and psychology. Traders who sold at old resistance may now buy back if it holds as support, and breakout buyers add on the retest. This role reversal is the same mechanism behind support and resistance — memory of price.
Entry and stop logic
Rather than chasing the breakout, wait for price to return to the broken level and show it holding — ideally with a rejection candle. Enter on confirmation and place your stop on the far side of the level, since price closing back through it means the flip has failed. The retest often gives tighter risk than the initial break.
Broken resistance becomes support and broken support becomes resistance — the retest lets you trade that flip with defined risk.
Not every breakout offers a clean retest; strong moves sometimes run without looking back. That is fine — skipping a trade that never gives your setup is itself good discipline.