Why do Benvolio, Romeo, and Mercutio attend the Capulets' party?

Romeo, Mercutio, and Benvolio attend the Capulets' party in Shakespeare's "Romeo and Juliet" for various reasons. Initially, they decide to go to the party because Romeo wants to see Rosaline, whom he is infatuated with at the time.

In an attempt to assist Romeo in letting go of his fixation on Rosaline, Benvolio states that Romeo will have the opportunity to compare Rosaline to other girls at the party and come to the realization that she is not the most attractive. Despite Benvolio's suggestion that attending the party might help Romeo move on from his unrequited love for Rosaline, Romeo decides to go in the hopes of seeing Rosaline and perhaps finding a new object of affection.

However, the decision to attend the party becomes a crucial turning point in the play when Romeo and Juliet meet and fall in love at the Capulet's celebration. The encounter sets off a series of events that lead to the tragic fate of the two young lovers and intensifies the longstanding feud between the Capulets and the Montagues.