When choosing a product fragrance you should first consider the end user. 
Who will be using the product? Think about the age group your target consumer belongs to. Products formulated for infants carry dramatically different fragrance notes and fragrance loads than a product formulated for a teenage boy. Create an image in your mind of the exact person that you envision using the product you are creating and get really specific about how that person looks, how they dress, their income and living situation. A very detailed image of the intended recipient of the product will help you define the scent profile for that product.
 
Think about the personality of your company or product.
Is your company rustic or refined? Do your products evoke crunchy hippies or sophisticated debutantes? Are they youthful and fun or elegant and refined? What image do you want to evoke when someone smells your product? A hand soap heavily laden with rose and lily is more likely to appeal to mature females than millennial males. Products heavy with oud, spices and resins are more likely to appeal to beard connoisseurs than to mommy bloggers. You should have a strong grasp on your brand identity long before you determine your product line and fragrance profiles.

What do you want a customer to know or feel about your product? 
Your product might be an ultra-efficient 3-in-1 cleanser that will save them time. Perhaps it’s a luxurious facial serum with a 3 step application process. Will your bath bomb remind the user of a seaside escape in the tropics? Maybe your pink Himalayan sea salt soak reminds them of a luxurious spa retreat. Scent evokes an emotional response in the end user and the scent chosen by the formulator should take emotion into consideration.
 
What type of product are you scenting? 
While buttercream frosting might make a delicious smelling lip balm, it’s not likely many consumers would want their deodorant to smell like bakery. A seductive musk and vanilla scent may make sexy smelling beard oil; most parents wouldn’t want their baby wash to smell seductive. A sugary, fairy floss body spray is likely to appeal to a tween, but maybe it won’t appeal to a professional masseuse who works with athletes. Think about the intended use of the product as it pertains to the end user.
 
Is it possible to link the scent to the purpose of the product? 
A relaxing bubble bath is more likely to be effective if scented with traditionally relaxing odors like lavender and chamomile than if it were scented with an invigorating blend of rosemary and mint. A deodorizing room spray is much more effective when scented with lemon verbena or Douglas fir than if it were scented with rice flower and shea or warm vanilla sugar. Think about and consider the function of the product in relation to the scent you select so that the user experience matches the product function.
 
When will you be selling the product? 
Pumpkin scented products are unlikely to be very popular around Valentine’s Day. Think about scents that correlate with national holidays. Many fragrance suppliers even provide lists of fragrances and their compatible holidays. Chocolate, champagne and roses evoke Valentine’s Day while ocean scents, tropical blends and sunny citruses are reminiscent of summer. Lily, violets, paperwhites, green grass, herbal teas and dirt remind us of springtime while cranberries, pomegranates, pine and peppermint are associated with winter holidays.

Where are you going to sell the product? 
Do your products belong in a farmer’s market or should they be in an upscale boutique? Are you setting up a booth at the local renaissance fair or tourist destination? Do you plan to sell your products in a gym or will you be featured at a local hair salon? The venue can lend inspiration to the fragrances you select. For example, products that will be featured at a winery might do better if they are offered in a collection of wine-themed scents like chardonnay, Bordeaux, champagne and merlot. Products sold in the gift shop at a lavender farm make more sense if they are scented with lavender, lavender blends and other herbal blends. Rose, lily, violet and carnation make sense in a Victorian bed and breakfast. Complex, designer-inspired scent blends lend themselves to high-end hotels.

Trends in fragrance often follow current fashion trends which in turn are driven by color trends. The annual color trends are released by Pantone, the leader in color communication and creator of the PMS color system. The color of the year for 2017 is “Greenery,” a fresh and zesty yellow-green shade that evokes the first days of spring. By studying and acknowledging the seasonal fashion and color trends, you can create scented products that complement the current retail trends which in turn can help to boost your sales.

By taking into consideration your target consumer, your brand identity, the personality and type of product to be scented, the products purpose, the time of year you will market and sell the product and the location where the product will be presented for sale, you can help minimize and even eliminate “dud”fragrances from your product line.

References:
https://www.pantone.com/color-of-the-year-2017
https://www.wholesalesuppliesplus.com/store-search.aspx?CatalogID=-1&FBK=Clean+And+Green+Fragrance+Oils