Exactly, given enough time, a head and shoulders top can trade into a symmetrical triangle, or a bull pennant can trade into an ascending triangle and come back into the pattern and tag your stop before the pattern is resolved, which, by the way, could be in the other direction. Do you reverse? Oh sure, that could work but it probably won't. It'll break support, bounce back and tag your stop again before making a monster move, long after you've given up on the stock. What went wrong? You got wrecked by randomness. Patterns look great in hindsight.
Quote from Asparagus:
interesting thread. learning to trade i racked my brains trying dozens of different patterns and looking at thousands of charts. i thought very rigidly about the patterns when i first started out and i used to get smoked very frequently. as i began to think more flexibly about the patterns they began to lose their usefulness (that could be a head and shoulders top or a consolidation before a continuation...). at this point i gave up on charting, began to focus on the fundamentals and started taking longer term positions. i rarely reference charts now other than to make sure the price action is confirming my fundamental view. the realisation that i could not predict the future based on the charts took a great deal of stress out of my trading experience.
asp