The following is an excerpt from a post by Louisa Leontiades, which corresponds with my views on the topic:

My Problem With Monogamy - Comfort Instead of Happiness


Everyone asks why. Why take the risk of having an open relationship when you have children? They perceive open as 'non-committed'. Why take the risk of being polyamorous when you are so happy together? They perceive polyamory as a selfish choice rather than a realistic choice supporting an inclination. Rather than argue those misconceptions, my answer is this.

The reason we are so blissfully happy is because we have an open relationship. Being monogamous is a horrible risk. And for us at least, a greater one than polyamory.

Monogamy is designed to keep couples together by creating barriers of exit; socially; financially and psychologically. One cannot look at the divorce statistics to ascertain how successful it is; this only proves how many couples remain married. Not how many couples remain happily married... Judging by how many marriages now end in divorce since it became more socially acceptable, that's not many over the long term. Nor does it show how many couples are monogamous by law and yet have some element of infidelity within their configuration, be it emotional or physical.

No. In the final analysis, statistics mean very little (and being a financial analyst by trade, I know that underlying motivations for variance can tell a completely different story). I cannot, and will not prove anything to anyone with statistics.

People may choose to be monogamous or polyamorous. But the monogamous system has evolved from a principle involving control and property/resource management. It has not stemmed from values of freedom, acceptance and love. To my mind a system which has evolved freedom, acceptance and love sounds far better than a system which is grounded in control and property/resource management. We are a culture who tries to assuage uncertainty and establish boundaries to control our fear. We are living in a fear based culture. And our society exemplifies this in numerous ways.

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