Common Red flags I look for:
1. Too defensive / married to a hypothesis. Shows lack of coachability.
2. Unreasonably confident in an anaysis when the appropriate data wasn't available (i.e. too "gut feel" oriented -- leave that job to the CEO). Shows lack of empathy / self-awareness.
3. Not MECE enough, OR far too focused on being MECE so much so that everything feels over-structured and robotic. Shows lack of originality.
4. Very "list oriented" vs bucket oriented - similar to point #3. Shows lack of structured thinking.
5. Error in analytics - shows lack of focus
6. Executive presense (depending on level) -- shows lack of confidence / comfort with oneself.
7. Weak personal stories -- shows lack of real-world experience / lack of self-reflection.