The phenomenon you described can be attributed to various factors related to human behavior and social interactions. Here are some possible reasons why people may initially appear nice and friendly but later reveal negative traits:
Impression management: In the initial stages of meeting someone, individuals often try to present their best selves to make a positive impression. They may act friendly and accommodating to create a favorable image. However, as time goes on, they may feel more comfortable showing their true personality.
Hidden motives: Some people might have underlying motivations, such as gaining something from the relationship or using others for personal gain. They may be nice and friendly to establish trust before revealing their true intentions.
Social norms and expectations: Society often encourages polite and friendly behavior, so people may conform to these norms initially. As they become more familiar with others or feel less pressure to maintain appearances, their true personality may emerge.
Defense mechanisms: Individuals may use niceness as a defense mechanism to protect themselves from potential conflicts or criticisms. Once they feel secure or face challenges, they might display less favorable traits.
Incompatibility: Over time, differences in values, beliefs, or interests can become more apparent. What initially seemed like genuine friendliness might have been an attempt to connect, but as the relationship progresses, the incompatibilities become evident.
Stress and life circumstances: External factors like stress, personal issues, or difficult life circumstances can impact behavior and attitudes. As people face challenges, they might become more irritable or self-centered.
Lack of authenticity: Some individuals struggle with being authentic and may present a façade to fit in or gain acceptance. As the relationship develops, they may let their guard down, revealing their true, less amicable self.
It's important to note that not everyone follows this pattern, and many people remain genuinely kind and considerate throughout their interactions. However, being aware of these possibilities can help you approach new relationships with a balance of openness and caution. Building meaningful connections with others often involves understanding their behaviors over time and setting healthy boundaries to protect yourself from potentially toxic individuals.