: A third touch is widely considered the gold standard for confirmation, signaling that the trend is established and not just a coincidental connection of two points.

: Touches should be well-spaced rather than clustered. Steep trendlines are prone to "noise" and are often less reliable than those with a moderate slope.

Guide to exploring the Trendline Trading Strategy - Capital.com

: A valid trendline requires at least two points (swing highs for downtrends, swing lows for uptrends).

A trendline's validity is dictated by its structure and the number of times the market respects it.

To avoid "fakeouts"—where the price briefly crosses the line before snapping back—traders use several confirmation filters: