First we should capture the attention of the visitors and make the interest for our product and services then grow desire, and call for action.
At first we may have some questions:
- Why do I need your product?
- Why should I wait for it?
- Why should I pay more for your product?
- Is it still effective (suppose, I don't trust natural products)?
The visitors or the customer wonders whether, "Is it worth the investment," "Do I (customer) really need it to get results?" and so on.
So, Simply put, don't be afraid of using long copy. Aim to say what needs to be said to move to the next step, just it. If you have some doubt then simply use website optimizer.