Needs or Wants — There’s a Different Approach for Each!
If  your prospect wants what you offer, then you can invite a response in the form of an immediate buying decision.  For example, if you’re offering a wonderful Caribbean cruise, that’s highly desirable.  And a good Call-To-Action would invite someone to book with you.

However, if your prospect needs what you offer, then you should use a different approach. Typically, ‘wants’ are associated with ‘soft’ services like ‘business consulting’ more than ‘hard’ products or goods like a ‘getaway weekend’ cruise. Remember, we want to be healthy but we need a colonoscopy.  The former is obvious and desirable.  The later is not.

The Two-Step Call-To-Action
I’m assuming you’re offering a service more than a product.  So what you’re offering is really the (needed) MEANS to some (wanted) END that your prospect would like to enjoy.   This requires an offer to get something — usually information — that would help someone get what they want.

A CPA might therefore ‘offer’ an e-book on:
“The Five Biggest Tax Deductions Business Owners Always Seem To Miss”

Inviting people to download that e-book would certainly identify people who might logically need other services that a CPA can render.  But, absent an opportunity to engage prospective clients in the first place, those subsequent conversations may never have a chance to occur!

KEY POINT:
When appealing to ‘wants’, always offer an item-of-value that is low-risk / no-cost to accept and suggests high-value if it is.  Once you have the ‘first’ step out of the way, you can make follow-up actions appropriate to the person’s ‘need-to-know’ and ‘readiness-to-go’ ahead with later offers to engage your services.