Blooming Flower

A every few years, I've been asked the question: "What is your favorite flower?". I'm not sure the decrease in the number of times I've been asked us due to me being a man now or just because I'm getting older. It's a tough question since I haven't experienced many flowers in my lifetime; I can't fully appreciate what I haven't seen in person.
The majority of of responses seem to be based solely on the appearance of the flower. It's like how people choose Macs for the appearance only (functionality comes after design). Boring people choose roses, dandelions, sunflowers, and lily's. So when I think about my favorite flower, I don't choose solely on appearance but on much more. My favorite flower is the Night Blooming Cereus. For the majority of the year they are just green plants. But just like women (and men), they "dress up" very nicely for occasions. In the flowers case, it's about once a year for a few days (at most). They are very beautiful once they do bloom; it's like they have a personality. But the annual blooming isn't the the main explanation it's my favorite flower; it has more emotional meaning to me. My mother has had two of these plants in our house since they moved in which means it's about the same old as I am. It's hard to imagine the house without them though most people wouldn't even notice them majority of the time.
What is your favorite flower of all time? I hope you have a good explanation.