Every piece of research I have ever seen puts the conversion rate of an initial sales contact little higher than 2%.
It does not seem to matter if it is the old style letter box stuffing or sophisticated email outreach, 2%.
Does that mean 98% are not interested?
Not necessarily, it can mean that they are just not ready to buy right now.
Therefore there is a percentage of that remaining 98% that may buy at some point with some nurturing.
This opens the question not just of how you go about the nurturing process but how you split your time, creative, and financial resources between the two, which is where the challenging strategic choices need to be made.