Thus it is quite possible that very low neuroticism has
fitness disadvantages in terms of lack of striving or hazard
avoidance. Although very high neuroticism has evident
drawbacks, it may also serve as a motivator to achievement
in competitive fields among those equipped to succeed.
Thus the optimal value of neuroticism would plausibly
depend on precise local conditions and other attributes of
the person, leading to the maintenance of polymorphism.