If you are a salesman and you see life and politics as about the sell, you adjust the sell every time to a different customer-base. Most people find this perfectly natural in a business setting, and it makes a lot of sense. It's called marketing. You can and should sell the product to different audiences emphasizing which elements will appeal to each. 

But we often find the same strategy a little ethically dubious in politics and religion. Why? Because the product you are selling, in these contexts, is something in the future, not something we can see now, touch and examine and test. When you change both the pitch and the product for different audiences, and refuse to tell people what the final product may be, you need a lot of chutzpah and salesmanship to do the job. You need to have a facility for lying, while seeming utterly sincere. You need to have a face that can be re-set constantly to assess and sell to every door you knock on, especially if what you are selling does not, in normal reality, add up. Especially if the people you are selling to are in desperate straits, seemingly out of their control, in confusing times, where they are losing, and looking for hope and order and authority that will never crack or reveal weakness or lose its smile.