People who feel they aren't represented tend to uprise violently. You might be familiar with the concept: it was key in your country becoming a country.But seriously, what purpose does having a minority party in government serve?
I like the way the principle is expressed in Robert's Rules of Order (and other rules of parliamentary procedure): the majority has the right to make decisions, but all members have the right to speak and have their opinions known to everyone before the decision is made.