Every fragrance is described with a list of notes arranged in three tiers. The structure describes something genuine about how scent develops, and the specific lists are copywriting rather than composition.
What the structure actually describes
The real phenomenon underneath.
Fragrance materials evaporate at different rates. Lighter, more volatile molecules are perceived first and disappear quickly. Heavier ones persist for hours.
Which means a fragrance genuinely changes over time, and the three-tier description is a reasonable way of communicating that.
Top notes are gone within minutes. The heart occupies the following hours. The base persists longest and is what remains at the end of a day.
That much is chemistry rather than marketing.
Where the published lists diverge
Several ways.
Many listed notes are not present as materials. A fragrance described as containing a particular flower frequently contains synthetic materials constructed to evoke it, because extraction from that flower is impossible or prohibitively expensive.
Some listed notes describe an impression rather than an ingredient. Terms like leather, rain or sea air correspond to no extractable material and are accords built from several synthetics.
And the lists are marketing documents, written to construct an image, with materials chosen for how they sound as much as for what is in the composition.
Actual formulations are trade secrets and are not published.
Why synthetics dominate
Worth stating because natural is used as a quality claim here as elsewhere.
Synthetic materials offer consistency, which natural extracts do not, since harvests vary.
They allow scents that cannot be extracted at all.
They avoid materials from endangered species and protected plants, which is a genuine conservation matter and has driven substitution.
And they are frequently better tolerated, since many natural extracts contain known sensitisers.
Essentially every fragrance on the market uses them extensively, including those marketed as natural.
The regulatory position
Which shapes what can be used.
Industry bodies maintain restrictions on materials, updated as safety assessments develop, and certain materials have been restricted or prohibited.
This has required reformulation of long-established fragrances, and enthusiasts frequently observe that older bottles smell different from current ones.
That is real rather than nostalgia, and it is a consequence of safety restriction rather than cost-cutting, though cost-cutting also occurs.
Allergen labelling requirements in some jurisdictions require specific fragrance allergens to be named, which is why some ingredient lists end with a run of chemical names.
Concentration, which is what the names mean
The terms describe the proportion of fragrance oil in the solution.
Higher concentrations last longer and are stronger, and the categories are not tightly standardised, so the same term means different things between houses.
Higher concentration is not straightforwardly better. Some compositions are designed for a lighter concentration and become unbalanced at higher strength, since not all materials scale evenly.
Why it smells different on different people
A real effect with mundane causes.
Skin varies in oiliness, pH and temperature, all of which affect how materials evaporate.
Dry skin holds fragrance less well, which is why moisturising before application extends longevity noticeably.
And there is genuine individual variation in the ability to perceive specific molecules, with well-documented cases where a substantial proportion of people cannot smell certain common fragrance materials at all.
Which means two people can genuinely be smelling different things from the same bottle.
How to buy without being led by the copy
Test on skin rather than on paper, since paper does not reproduce the development.
Wait several hours before deciding, since the opening is the part that lasts the shortest time and is what shops are designed around.
Test one or two at a time, since the sense fatigues quickly and comparisons after the third are unreliable.
Use samples rather than deciding in a shop, which most houses provide and which is the only way to assess how something behaves over a day.
And ignore the note list, which describes an intention rather than a composition and correlates poorly with what you will actually smell.
Storage
Since fragrance degrades and most people store it badly.
Light, heat and air are what break it down, which makes a windowsill or a bathroom shelf the worst available location.
A closed box in a cool dark place extends life considerably, and the original packaging is generally designed for exactly that.
Sprays last longer than bottles with stoppers, since less air is admitted with each use.
A fragrance that has turned generally smells sharp or sour at the opening while the base remains recognisable, which is the signature of oxidation.
Application
A few practical points that make more difference than the product choice.
Applying to skin rather than clothing, since skin warmth drives the development and fabric holds only the top layers while risking staining.
Pulse points work because they are warm, which is the actual mechanism rather than anything mystical.
Not rubbing after application, which is widely repeated advice and does have some basis, since friction and heat accelerate the evaporation of the lighter materials.
And less than instinct suggests, since the wearer adapts to their own fragrance within minutes and stops perceiving it while everybody else does not.