The behavioral and social theoretical perspectives define personality as a number of traits that are acquired through conditioning and interaction with the immediate environment. Social learning, self-conditioning, and even peer pressure motivate people to make choices that ultimately affect their personality. Hence, the dynamics go both ways: our current traits, combined with interactivity, mold and re-mold our sense of self and our personality.
Therefore, a stable personality is described as one where traits are consistent and hardly ever change. This could be due to motivation (negative motivation, as in the refusal to change or peer pressure to remain the same), or because of a learned habit caused by culture, ethnicity, religious belief, or even due to daily fears; non risk-takers, for instance, are likely to stubbornly stick to a set pattern of activities and behaviors.
Similarly, a dynamic personality consists on acquired traits that come from social interaction, motivation, and conditioned habits. The dynamic personality is completely contrasting to the stable in that dynamics are flexible, risk-taking, challenge-driven, adaptable, and not scared of change. Under a behavioral/social perspective, this would be an entirely learned behavior because it is typical of all humans to be at least weary of moving off a comfort zone. The implication is that, even though some people might be more daring than others, it is through observation and motivation that we get the assertiveness to become dynamic. Dynamic personalities, such as INTJs and ENTJs often place the Locus of Control on their own abilities because they have found the self-esteem and self-actualization to dare and move outside the comfort zone.
Therefore, behavioral/social perspectives directly point at social learning, imitation, motivation, and extrinsic influences (which later become intrinsic) as the conduits that motivate people to either become stable or dynamic.