Why do lord Capulet and Paris think Juliet is still crying?

Lord Capulet and Paris believe Juliet is still crying due to her grief over Tybalt's death. They interpret her tears as a sign of mourning for her cousin, not realizing that she is heartbroken over her situation with Romeo. Their misunderstanding highlights their lack of awareness about Juliet's true feelings and the depth of her emotional turmoil.