Share your insights or perspective on the financial matter presented in the input.

Is it possible to know the probability that a trade is successful?
If you had a trading system, and by trading system I mean the criteria setup that you will take a trade on, then once a setup comes up at what price will you open the trade and at what price you will close the trade. As an example, if you want to buy once price breaks through resistance at $10.00 you might place your buy order at $10.05. So once you have a written trading system you could do backtesting on this system to get a percentage of win trades to loosing trades, your average win size to average lose size, then from this you could work out your expectancy for each trade that you follow your trading system on.