Final answer:
College students may not reach full formal operational thinking due to continuous cognitive development into postformal thought and external influences.
Step-by-step explanation:
Many college students and adults may not be fully formal operational because the development of cognitive abilities can be a continuous process that extends beyond Piaget's final formal operational stage. However, not all college students and adults are fully formal operational. Developmental psychologists have suggested a fifth stage of cognitive development called the postformal stage, which involves decision-making based on situations and integration of logic and emotion. Many students and adults may still be working through this stage, which is why they may not exhibit full formal operational thinking. Adults often enter a phase called postformal thought, where decision-making involves integrating emotion and context-dependent logic. Moreover, external factors such as standardized testing, belief systems, and societal norms may interfere with or delay the development of critical thinking and abstract reasoning abilities.