Ever know someone who could walk down a hallway and his/her cologne would precede their entrance? Well, they're probably not wearing the right cologne and/or they probably didn't spend enough time making the right selection. You see, we're all different, with different body chemistry which reacts differently to a myriad of things; jewelry, food, temperature and (in this case) fragrance, just to name a few.
All fragrances are made of three basic ingredients; fragrance oils, alcohol and deionized water. The higher the concentration of fragrance oil used, the longer the fragrance will last on your skin. However, a higher concentration does not necessarily mean an overpowering scent, merely one that lasts longer.
The correct way to test any fragrance is on your skin. A scent strip or a whiff from a bottle cannot adequately duplicate its uniqueness on the wearer. As the warmth of your skin allows the alcohol and water to evaporate, the essential oils interact with your body chemistry until everything blends together to achieve the final scent.
A final thought: when should others begin to smell your fragrance? Without being either offensive (as in the example above) or nearly non-existent, your fragrance should be delightfully noticed within about eighteen inches, or about the "personal space" boundary that is typically acceptable in public.