Incentive plans as the name suggests should be designed to incent sales personnel to behave in a certain fashion. If they are hunter types, going after new business, you want them to be closing new sales and therefore you want to incent them to get new customers by paying them heavy commissions on each new sales and a not so high base compensation.
On the other hand, if they are harvester, gatherer types, they are there to forge and solidify long term customer relationships and their compensation should be heavily weighted towards base compensation so that they are not incented to pressure the customer into making decisions that are not in the customers’ best interest in both the short and long terms.