Final answer:
A qualitative researcher who does not consider their impact on the observation lacks reflexivity. This concept is essential to understand how the researcher's presence may influence study outcomes and participant behavior.
Step-by-step explanation:
A qualitative researcher who assumes that everything he observes would have happened exactly the same way if he wasn't there observing lacks reflexivity. Reflexivity in qualitative research refers to the understanding and acknowledgment by the researcher of their own influence on the research process and outcomes.
This includes understanding how the presence of the researcher might alter the behavior of participants, which is a crucial aspect to consider in observational studies to maintain objectivity and the integrity of the data.