I make mistakes. I'm a programmer, half of what I do is giving birth to new bugs, and I hate it. So of course I try to improve that percentage. To identify and avoid error-prone routines, to interrupt mistakes before they've gone too far, etc.
Brexit scares me. Britain is an entire country with all the democratic mechanisms and institutions, with a long tradition, with no external pressure, with a full set of checks and balances, no lack of time or other resources except what they imposed on themselves. If experience, review, discussion or routines guard against mistakes, then noone should be more able to avoid big mistakes than Britain. Yet with just three weeks to go, they still seem headed for an utter mess. I can't bear to watch it.