There is such a thing as a good and bad primer. The former are the perfect candidates used to amplify the region you are interested in with 100% efficiency, without amplifying anything else in the genome. The latter, however, are those which completely destroy qPCR results. They are inefficient, have low specificity and cost you valuable time through further optimizations.
In the video below, I will go through the attributes of what makes a good primer pair.
Probe-based assays also require an additional primer, known as a probe. For these, there are a few additional recommended attributes:
Here are the important points to summarize this lecture: