It is usually easier to find more business with existing customers that it is to find new ones, or to devote the resources to reducing customer churn. Nevertheless, most enterprises overspend their limited resources seeking new customers at the expense of their existing customers. 

If you must chase new customers, there are 3 very simple questions to ask:

1. Do they have a problem you can solve?

2. Do they have the money and desire to take a risk with a new supplier?

3. Can you reach and communicate effectively with them?.

Three ticks, and you have some chance, two ticks and your time is better spent elsewhere, no ticks, wake up to yourself.