Because fragrances layer rather than cancel, and almost everybody's intuition about this is wrong in the same direction. When you put a second scent into a room that already contains one, the nose does not blend them into a single averaged impression. It registers both, separately, along with the interference between them - and interference is what people mean when they say a room smells synthetic, cloying or confused. Two competing profiles read worse than either one alone; three read worse than two. That is the whole mechanism, and it explains the pattern I see in almost every clinic that writes to me about this. Somebody buys a plug-in for the reception. A few weeks later the washroom gets a gel because the plug-in does not reach it. Then an aerosol appears in a drawer for after the bins are emptied, then something in the corridor because the corridor feels flat, and by the end there are four sources running four different profiles and the founder cannot work out why a clinic with more fragrance in it than ever smells less pleasant than it did two years ago. The escalation feels rational from inside because each new source genuinely does change what you notice - for about a day, until it settles into the mixture and the baseline is one item longer. There is a second thing worth being blunt about. Your staff are in this all day and you are not. The desk usually sits within a metre or two of at least two sources, so your front-desk team spend nine hours in the most concentrated part of a mixture that patients only cross the edge of for forty minutes. If you ask them honestly - and mean it - the answer is frequently that they have been putting up with it. Fragrance sensitivity is real, it is never minimised, and nobody should be asked to tolerate a room for the sake of an ambience decision. So the fix is subtraction and it costs nothing: take every source out of the building, including the ones in drawers and the clip somebody stuck behind the monitor, and run nothing at all for two weeks while airing the place properly. That gives you a real baseline, which is something you have not had for years. Then decide from it. If the answer is that you want a character in the reception, it is one source, one profile, one low level - one SOSA Vaayu at ₹11,999 past roughly 1,500 sq ft with a key-lock so a second source cannot quietly appear, or one SOSA Sukoon at ₹1,899 for a single small reception, where a Vaayu is the wrong buy. And if the answer after two weeks is that the clinic is fine as it is, then buy nothing; a room that smells of nothing in particular is already the correct result. Reception and waiting only, clinical rooms unscented, an ambience decision with no clinical or air-quality claim, never a mask and never a substitute for cleaning or ventilation, and your judgement as the treating clinician overrides all of it. Ask for a clinic scenting plan after the two weeks, not before.