We have all heard it before, if you fail to plan, you are planning to fail, or plan your work and work up your plan. There are several axioms to remind us the importance of planning. The underlying logic reveals the backbone of the importance of having a plan. How can you possibly get to a destination if you have no roadmap to get you there.
Many sales people are wired to gravitate to action ( making the sales call) not writing out a plan.
I agree in the beginning I had a hard time adjusting to planning first and then executing the plan. I think the real reason was that I did not want to be accountable to my plan. It is so much easier to justify a tough day without a method of evaluating the calls planned and to the end result.