Deception and bias are of particular concern. These sources may also convey one message in English for US or international consumption and a different non-English message for local or regional consumption. It is important to know the background of open sources and the purpose of the public information in order to distinguish objective, factual information from information that lacks merit, contains bias, or is part of an effort to deceive the reader.
Bill Mera has some good strong points on this. My experiences in Sub-Sahara and Estonia often led to confrontation at the embassy. Reporting variations were at times near opposite and worse, irreconcilable. Those with greater rank, simply jammed their version down the tube.

The FM is certainly better than some of the "100 dash Ones" from my days in the early 80's.