Chart, page-36

As is often the case, common terminologies with subjective meanings are
often the cause of much misunderstanding.
In the eyes of many professional traders, valid breakouts (ie: ones that
are considered a reliable signal for entering a trade) are not as simple
as the mere penetration of a particular boundary.
Factors such as the strength of the close, distance beyond boundary, wicking,
comparative volume and average true range, are often considered.
Considering different ways of drawing lines and patterns can create
extremely different conclusions and to err on the side of caution is generally
a good idea. Confirmation bias is one of the trader's constant enemies.

For anyone who might be interested here is link to an article by the
legendary Peter Brandt which is very insightful into how seriously
the best traders look at these and other factors to increase the probability
of success and manage risk:
https://www.peterlbrandt.com/copper-a-case-study-of-a-difficult-breakout/

I saw a dramatic improvement in my trading results when
I practically eliminated trend-lines from my charting meathodology.
Execpt for the most dramatically obvious, recurring and long-standing
ones, I find them to be too subjective.

I have on a number of occasions seen something I did not notice thanks
to the analysis of other posters, now matter how different to mine.
That in itself, is priceless.