This means that Marketing can benefit from promising a little less than the company can deliver Imagine if the customer from the previous example had the internet installed two days earlier than he had been promised and on top of this by a friendly and serviceminded technician

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This means that Marketing can benefit from promising a little less than the company can deliver. Imagine if the customer from the previous example had the internet installed two days earlier than he had been promised - and on top of this by a friendly and service-minded technician.