Every one is prospective customer

If you are selling any product, find the target market and isolate the target prospective customers. Once you completed this, you can position your product. Most of the customers may not be using your product not because they dont like or dont need the product, but for many reasons like

• They may not be aware that such product exists.
• They are not aware of the benefits it offers over the competition.
• We are trying to sell to wrong target.
• Your product is new and untested in the market.
• Competitor is well known and well establised.
• You are unable to reach the customer.
• Your pricing is very high

so and so the list can go on.

Understand what exactly is the reason and position the product accordingly. Say the competitor is well established and having a great run, see a niche market where he overlooked, or see for the unsatisfied customers of the competitor, or else focus on a small niche where you find the competitor is weak and put maximum efforts in that market.
There will be solutions for every problem, only important thing is to identify the problem look for a solution and put it into action and put 100% efforts into it.