1) Physical appearance plays an important role in initial attraction and dating success, though personality becomes more important over the long-term. Studies show men prioritize physical attractiveness more than women, especially for short-term relationships.
2) Different types of love - passionate, companionate, and commitment - factor into relationship satisfaction according to Sternberg's triangular theory of love. Healthy relationships incorporate all three.
3) Dating customs have evolved significantly over time from parental-arranged marriages to today's more casual relationships. This correlates with rising divorce rates as compatibility issues become clearer over the long run.