Hi and welcome!
To answer your question, every person is different. Some people only need a small amount of a phero to find that point where the most and best effects occur, others need more. So, if someone typically needs 4 sprays to get the best effect, then it makes sense to just get 4x, it is more economical, and you only need one spray.
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It is a gradual process that requires patience, but necessary if you don’t want to waste your product, and if you want it to work for you.