well yeah, nothing is guaranteed when focusing on technicals alone - That's why I've also touched on the fundamentals of this coin (I've gone over it a lot in my prior posts but just touched on it again as a refresher).
Having said that - you can't ignore technical analysis altogether - as often the patterns are unmistakable, and mathematics is used a lot to make various predictions - not just with the performance of assets but with the wider society as well.
Oh well that's good. What percent of the time does technical analysis accurately predict these patterns?
How long is a piece of string?
The question you ask is often discussed, and studied, but nobody can ever really give you a definitive answer.
https://www.investopedia.com/articles/active-trading/062215/debunking-8-myths-about-technical-analysis.asp
https://www.sciencedirect.com/science/article/pii/0261560692900483
Like I said - I'm not a technical analysis fanatic - I rarely base my investment decisions on that alone - I was invested in vertcoin before I saw any of the above stuff - Most of the technicals with Vertcoin I would have seen some time ago from other analysts and been watching ever since...