The present study examined the relation between the type of relationship onset on the one hand and the degree to which partners have similar personalities and relationship quality on the other hand. It was hypothesized that partners who fell in love at first sight, relative to partners who got involved more gradually, entered into intimate relationships more shortly after they met, would have mates with less similar personalities, especially with regard to levels of extraversion, emotional stability and autonomy, and would report relatively low levels of relationship quality. In a sample of 137 married or cohabiting couples, it was found that, as predicted, partners who fell in love at first sight became romantically involved more quickly, and showed more dissimilar personalities with regard to levels of extraversion, emotional stability and autonomy. Partners who fell in love at first sight did not report lower relationship quality. Instead, partner personality trait similarity was related to relationship quality as a function of both relationship onset and specific personality traits.
Source: “Love at first sight or friends first? Ties among partner personality trait similarity, relationship onset, relationship quality, and love” from Journal of Social and Personal Relationships