How do subtle rule changes in any system (a game, an organization, society) dramatically alter behavior and outcomes?

The offside rule's history shows how even small tweaks, like changing from three opponents to two, can entirely reshape a system. This insight can be applied to understanding policy changes, company regulations, or even social norms. Consider how new laws or unspoken rules in your own life or work environment have subtly, yet profoundly, shifted behaviors, incentives, and ultimately, results. It highlights the often-unforeseen ripple effects of seemingly minor adjustments.