The term buy is from Old English bycgan (past tense bohte) "get by paying for, acquire the possession of in exchange for something of like value; redeem, ransom; procure; get done," from Proto-Germanic *bugjan (source also of Old Saxon buggjan, Old Norse byggja, Gothic bugjan), which is of unknown origin and not found outside Germanic.
The "why before the buy" is the marketer's goal. Survey technology can get to the reason consumers buy products. What are the nuances in the product causing customers to buy or not to buy a product? The reasons could be as simple as a bitter taste, color of the packaging, cleanliness of the store, wait time, etc. New survey tech can get to the true reason we buy a product, removing as much bias as possible.
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Possession of hope, redeem a dream at the edge, nuance of exchange