Prospect's requirements is probably the most important information a sales person should get to turn a prospect into a customer. At first glance, getting user's requirements is an easy task: the only thing you need to do is to ask. However, experience shows that there are several factors which make this simple task difficult and make it hard for sales person to sell the product to prospects.
1. Few users who downloaded your trial version actually formed a clear vision of what they need (and these few either already uninstalled your program because it didn't meet their requirements, or they already contacted your technical support department themselves). 2. Neither sales person, nor prospect has enough time to send each other dozens of emails trying to clarify the requirements and make sure they talk about the same feature (moreover, statistics says only 5% of users will respond to your attempts to set rapport).
The answer is to ask the right questions, i.e. the questions that make the prospect define the key requirements and don't let him get into trifles. Once you are lucky to get the response, you need to thoroughly analyze the key requirements and offer the solution that exceeds the prospect's expectations (Ex.: Our spam filter not only blocks the spam emails but also automatically finds contact information on the spammer’s website and sends 10 emails in reply :-).