You smell something on a friend, buy it, and it is wrong on you. This is one of the most common experiences in fragrance and it is entirely real. The bottle has not changed.
Temperature does most of it
A fragrance works by evaporating. Materials leave your skin at different rates, which is what produces the sequence of top, heart and base that a composition is built around.
Warmer skin speeds all of that up. The fragrance arrives louder and faster, the opening is compressed, and the whole arc is shorter. Cooler skin holds it back, so it projects less and lasts longer.
This is the largest single variable, and it is why the same fragrance can seem overpowering on one person and barely present on another.
Skin type is second
Oily skin holds aromatic materials considerably better than dry skin. The oils give the molecules something to cling to, and the result is longer wear and a fuller development.
Dry skin releases everything faster. If a fragrance seems to vanish on you within two hours while everyone describes it as long lasting, dryness is the most likely explanation, and it is also the easiest to do something about.
Unscented moisturiser before applying genuinely works, and it is the only application advice worth repeating.
Skin chemistry, which is smaller than people claim
Skin pH varies between people and it does affect some materials. The effect is real and it is usually overstated: it is noticeable on a few materials, particularly some ambers and certain synthetic musks, and negligible on most.
What is more significant is what is already on your skin. Soap, deodorant, laundry detergent in your clothes and any residue from yesterday’s fragrance all combine with what you apply, and heavily perfumed soap in particular will change the opening of anything you put over it.
The part nobody mentions
You cannot smell yourself properly. Within twenty minutes your nose has adapted to your own fragrance and largely filtered it out, which is why people habitually apply more than they need.
So when you smell a fragrance on someone else, you are getting an accurate reading. When you smell it on yourself, you are getting a poor one. The friend’s version seeming better is partly that you can actually perceive it.
Things that genuinely change it
Diet has an effect, particularly heavily spiced food, though it is smaller than internet advice suggests.
Medication and hormonal changes affect both skin chemistry and your own sense of smell, and this is the usual explanation when a fragrance you wore happily for years suddenly seems wrong. Nothing has changed in the bottle.
Illness, even a mild cold, changes your perception considerably and is a bad time to judge anything.
Testing it fairly on yourself
A few things make the test more honest.
Apply to clean skin, not over yesterday’s fragrance and not straight after a heavily perfumed shower gel. Both will colour the opening and you will be judging a combination rather than the fragrance.
Use the same spot each time. The inside of the wrist and the inside of the elbow are both warm and both work; switching between them introduces a variable you do not need.
Do not test on a day when you are ill or congested. Your perception is genuinely altered and it is not a fair reading.
Why two people can disagree completely
Beyond skin, people differ in what they can perceive. Specific anosmia is common: a substantial minority cannot smell certain musks at all, and smaller groups are insensitive to particular woods and ambers.
So when someone says a fragrance has no lasting power and someone else says it lasts all day, they may both be describing the same bottle accurately. One of them is not detecting the base.
This is worth remembering before dismissing a recommendation, and before trusting one.
What to do about it
Test on your own skin and nowhere else. A paper strip has no temperature, no oil and no chemistry, and it shows you a version of the composition nobody will ever wear.
Give it four hours before deciding, because the differences between people are largest in the heart and base rather than in the opening.
And do not buy something because it smelled good on someone else. That is the single most reliable way to end up with a bottle you do not wear, and it is why every bottle HOUSE OF ZIGGIMAY sends comes with two 1.5 ml samples you choose yourself.