Despite growing acceptance, particularly among young adults aged 18-29 in the US, nearly half of open relationships fail within their first year. Sexual scientist Justin R. Garcia highlights three primary reasons for this high failure rate: an evolutionary drive for pair bonding that conflicts with managing multiple intimate connections, the significant time management and planning required to satisfy multiple partners, and the misguided hope that open relationships can fix existing relationship problems. While non-monogamy is not inherently doomed, success hinges on frequent, transparent communication and a genuine desire from all involved, though only about 1 in 25 romantic relationships in the US are currently non-monogamous.