1. The public is generally unaware of this because such knowledge is usually only possessed by researchers and policymakers. Often, there is so much research going on at any given time that the general public cannot follow all of it. Moreover, such research is sometimes not publicized or popularized.
2. There are several difficulties when it comes to informing the public. For example, researchers often do not have the resources to popularize their research and make it known to the general public. Moreover, studies that do not support a particular political perspective might not be easily accepted by certain political groups.