Something found during the course of the year, or that represented us or the year. Something "discovered." We looked forward to opening our ornament every year, because there was ALWAYS a story. When my sister got married, my mom placed all of her ornaments in a box, each wrapped separately in tissue paper, and gave the box to her as a gift, so that she could begin the tradition anew. Each ornament is a memory of a Christmas we shared as a family.
My mom is no longer with us... but her tradition is something we carried on with our kids, and their grandparents were thoughtful to share themselves with our grandchildren in this way. When we decorate our tree, it isn't the sort of tree where every ornament matches... others may not look at it and think of it as a piece of art or matching any particular decor. In fact, it's entirely mismatched. And that's the point, because our Christmas tree is filled with more than ornaments... it's filled with memories and lifetimes. And decorating it... unwrapping each ornament, brings every story of our lives that we can smile and share to life.