Final answer:
Postdoctoral fellow Jean Twenge became aware of decision fatigue after experiencing research fatigue while participating in a research project.
Step-by-step explanation:
Postdoctoral fellow Jean Twenge became aware of decision fatigue after experiencing research fatigue while participating in a research project. The constant challenge of dealing with staff burnout and feeling overburdened and under-resourced led to a faster rate of burnout or research fatigue. This experience made Twenge realize the impact of decision fatigue and the need to manage it effectively.