Well, really, it's a result of selective enforcement and interpretation of law. One administration decides it doesn't care for a rule and decides not to enforce

Well, really, it's a result of selective enforcement and interpretation of law. One administration decides it doesn't care for a rule and decides not to enforce, or instead tailoring their interpretation to meet their desired outcome as to not appear asleep at the wheel. The next one comes along and decides it wishes to enforce based on another interpretation. This is a consequence of human systems, ultimately.