The first contact with a user is the beginning of the lifecycle. I encourage you to think of sales and marketing as support. You are, after all, supporting someone’s decision to buy but you are helping their search for answers and solutions. Buying your solution isn’t good for anyone if it’s not the right solution for them.
Thinking about the lifecycle of a user as starting before you actually, land them as a client or take their money should put you in the mindset that over delivers and supports with the user’s needs in mind. It should also get you thinking about their problem and pain and not about how your solution can solve. By integrating the prospective user with the actual client/customer user, you can more completely support the later. The potential user has a great deal to teach you – about their pain independent of your offering. It makes you user-centric, it makes it possible for you to think of the user before you think of what you’re selling them.