"Salespeople will always argue that offering a small discount doesn’t hurt and is the right thing to do for the customer.
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It doesn’t matter what the reason or how passionate the salesperson might feel about it, a discount is still a discount and it costs money!
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A discount offered to a customer is not a discount on the full price. It’s a discount on the profit, unless there is something else of value equal to the discount that is being removed from the offer. Problem is that scenario is rarely the case.
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A salesperson looking for a 5% discount may not view it as an issue to their company and thus feel it’s no big deal. Now, let’s frame the discount as being a 33% discount on profit and it suddenly becomes “game over.”"
Trechos retirados de "What Does Discounting Really Cost?"