Marketing 101:The concept of JND

I'm sure we all have come across memes telling us how you get nothing but air in a chips packet but did you ever find fewer chips in your consecutive purchases?

The concept that probably explains this is the "Just Noticeable Difference" popularly known as JND. For the more finicky people, it can be defined as the differential between two stimuli that can be noticed by the human brain. It is a widely taught concept in consumer behaviour and psychology.In marketing, JND is applied over consecutive purchases and not that prevalent in white goods per se. I find it being used extensively in FMCG. 

There are two major marketing implications of this

1. Keeping improvements and promotions above the JND.
2. Keeping negative changes below the JND. 

So I went to purchase a face wash I use frequently and right off the bat I could notice the bottle was bigger. There was a promotional 20% extra on the product and even though the dimensions, as well as the contents, are 20% more than that of my previous purchase I did recognize a significant change (perceptually more than 20%) which led me to believe I was getting more for my money and I walked out of the store a happy customer thinking I got a steal. This might not have worked for say a 10% or a 15% and higher percentages would have been infeasible. 

On the other hand chips, beverages and many others have seen a significant drop in their net contents. This may be attributed to rising costs and at the same time the magic price point of 10 rupees (Maybe something on this in the future) not wavering. But never have we once noticed this change over two consecutive purchases because this would perceptually lead a customer to believe he is being given less for his money. 

This is the same phenomenon that even helps to explain why you can see all those nuts on the surface of the chocolate when they are first introduced but slowly they fade away. 

JND is not only applied to product decisions but on things as simple as logo designs. Logos are things which help identify your brand. So a drastic change might be beneficial for a reposition but generally they are kept subtle enough to not draw any attention and yet be contemporary. 

I would love to hear your views in the comment section. 

Thank you for reading.