When RSI breaks through key trendline levels, it often signals a shift in market momentum. A trendline breakout in RSI can indicate either strengthening buying pressure or weakening selling pressure, depending on the direction. Traders watch for these breakouts as they may precede significant price moves. The strength of the breakout—volume confirmation and clean breaks versus false breaks—matters just as much as the breakout itself. Understanding where RSI trendlines form and recognizing when they snap is part of reading market structure on shorter and longer timeframes.