A recent blog post by Seth Godin centered around the question, "What do you need me to do."  Seth went on to describe how detrimental to the sales process this question could be, he stated, "you should be offering solutions not asking for tasks."

This question is similar to, "Is there anything else I can do for you."  I'm sure 90% of the time the response to that question is no.  What kinds of opportunities did you just miss out on? 

The customer doesn't know everything about you, your company and all your capabilities, so why would you expect them to tell you what else they need?  They don't know, you do! So Ask!

If you have done a great job at discovering their needs you should be able to offer up either the next step in the sales process, or an additional product or service that may solve their needs.

If you put the closing or up/cross selling into your prospects hands chances are they won't take the next step.

So remember to take control of your sales process, or no one will.