Ask HN: 1994 Caribbean Cup – What are modern day examples in technology?

You know how soccer is played - two teams trying to score a goal while defending their net. The last 3 minutes of this particular game in 1994 looked very different, if not bizarre: Team Grenada was trying to score a goal in any net including its own, while Barbados players defended both nets. https://en.wikipedia.org/wiki/Barbados_4%E2%80%932_Grenada_(1994_Caribbean_Cup_qualification) Are there recent examples in technology (features, products, policies) where rules produced completely unintended consequences?