The truly effective trend line must meet two core conditions simultaneously:

1. Anchoring the essential starting point of the trend continuation: accurately corresponding to higher lows (HL) in an uptrend, and locking in lower highs (LH) in a downtrend, definitely not invalid points in random fluctuations;

2. Verification through practical experience of key structures: for example, a support zone pushing to a new high after a pullback, or a resistance zone triggering a new low after testing; only with structural resonance can the trend line possess practical value.

Meeting the above two points, the trend line will demonstrate extremely strong stability and can provide precise guidance throughout the market; conversely, if the connected points lack structural significance, it is merely a "pseudo trend line" that deceives oneself and will ultimately mislead decisions.

In fact, the core of the trend line is never about how accurately it is drawn, but whether it can penetrate the market's surface and accurately identify the true turning points of the trend. Understanding the trend structure, drawing the correct trend line is just a natural result - this is precisely the core logic of technical analysis!