As a facilitator, you always work from a kind of 'meta' position, consciously intervening in cognitive processes such as the thinking process, the learning process, the communication process, and so on. A common pitfall is that the facilitator of a meeting or workshop is also the content expert. If you are unable to maintain the meta-position, you get drawn into the content discussions, which is not the intention.
Another pitfall with lack of meta-cognitive skills is not being able to observe your own thinking process and reflect on your own cognitive preferences and limitations. As a facilitator, it is important to know your own thinking processes and thinking style so that you can adapt them to the needs of the group and avoid any blind spots.
A third pitfall is not being able to encourage participants to observe their own thinking processes and reflect on their own cognitive preferences.