Indeed, to describe the best indicator depends on user experience, perhaps those who are looking for the best indicator will try various kinds of indicators. However, many people just try without carrying out long-term experiments. When one indicator is deemed to have failed, then try another, and so on until they get bored because nothing is the best.
I think the best indicator is the price itself or the candlestick itself. Understanding the concept of demand and supply, basic support and resistance, if you do it with discipline it will be the best mainstay weapon when combined with money and risk management