When you've practiced magic long enough, you inevitably start to form relationships with spiritual entities, and much like relationships you have with people, its takes some work on your part (and their part) to create a healthy and sustainable relationship. There's also the question of how you form the relationship initially. There are some approaches to forming a relationship with a spiritual entity that I would find quite rude (these approaches involve commanding an entity to appear and do what you tell it to do), and other approaches I wouldn't do because I'd be concerned about how much power I was giving to the entity.
Personally I prefer a middle approach. I'm not going to worship a spiritual entity or deity and do what it says. If I wanted to do that I'd have stayed with the religion of my family. But neither do I believe in doing the medieval approach to evocation which involves summoning the entity and threatening it with other entities in order to coerce it into doing something. I figure why not just ask nicely and on top of that create a good relationship? I know, I know, some of you will say, "That sounds rather fluffy and ill-advised." But seriously why not simply dispense with all the theatrics and try and make nice? It's always worked for me and I've gotten the results I've wanted while also creating a solid relationship with the entity I've worked with.