Without any other data to go on, you can't really judge if a particular program is worthwhile. Unless you have a track record of conversions on different traffic sources, it very well could be that the program you are promoting is either just not worthwhile or else you are marketing it to the wrong people.
I have tested hundreds and hundreds of products for campaigns and most of them don't work for me. Be it because of who/what I targetted or just because the program is really not set up to be a succesful affiliate program/product.
If I find something converting, then I can move it to other sources, and then I will at the other sources if I don't get conversions.
If you have never got any conversions anywhere with this product, I would put it on the shelf and find another product. Perhaps in the future you will have an idea that allows you to attack it from a different angle.
I have campaigns I tried and could not get to convert, then I tried to market it differently later on and had it work.
Anyways, don't worry about the traffic source until you are able to get conversions. Before you can do that you need to have some traffic sources you trust to bring conversions to you across a wide spectrum of areas. Or else you are just guessing.