In most discussions, rather than looking for flaws in our own arguments, it's easier to let other people find them and then only then adjust their arguments if necessary. And that's basically how science works is people generate arguments and other people attack those arguments and then over a long period of time, we get closer to the real truth. But I would just slightly object to the characterization of the way we find arguments as flawed because it's biased but not every bias has to be a flaw.