Folk wisdom gives us mixed-messages when it comes to compatibility. We hear phrases like "birds of a feather flock together" telling us we need to be compatible with a partner in order to be successful. Then we hear contradictory phrases like "opposites attract" telling us we need not be similar to our partner, but rather different for relational success.
Although compatibility isn't necessarily a synonym to similarity, they are certainly in the same family.
Perceived sexual compatibility is defined as the extent to which a couple perceives they share sexual beliefs, preferences, desires, and needs with their partner. Another form of sexual compatibility is the extent to which similarities exist between actual turn ons and turn offs for each partner emotionally, cognitively, and behaviorally.