I agree real time results (like price action) is all that matters.
However, IF one were to Buy and Sell based on an excellent model one would do very well. . .say, 90% in 6 months time.
Unfortunately, since we both (like other traders) probably don't do that, something else must be operating in our decision making process.
Too often, I suspect, many traders are willing to take small profits and alas, too often, watch losses grow while they hope to see the position reverse so they can at least get back to even. Thus, the pull of intraday and swing trading can be a kind of trap.
The process. . .a pitfall of human nature.