Although these odiferous chemicals were originally only by-products of photosynthesis, through mutation and evolution they came to play an important role in pollination. A mutated gene causing a particular flower to produce a scent might give that flower a reproductive advantage by attracting insects necessary for pollination. Over time certain species of flowers developed unique smells to attract particular insects. For example, sweet-smelling flowers such as roses are engineered to attract butterflies. Some flowers even smell like rotting flesh in order to attract flies--not exactly the best choice for a corsage.
Maybe knowing something about the science behind flower fragrance will make the experience even more pleasurable. If not, clear your mind, inhale, and simply enjoy.