Digital nudges were initially conceived as simple, static interventions in choice architecture designed to guide user behavior without restricting options. However, advances in sensor technologies, big data analytics, and machine learning have ushered in a new era of hyper-personalized, dynamically adaptive nudging strategies. These evolving systems promise more responsive user experiences and enhanced decision quality but also raise pressing concerns about transparency, autonomy, and algorithmic fairness. This paper conceptually differentiates three waves of digital nudging—static, personalized, and dynamic—tracing their technological enablers and ethical challenges. A framework is proposed to guide the selection of appropriate nudging strategies depending on context, user needs, and ethical considerations. While intelligent, adaptive nudges offer powerful opportunities for positive behavior change, their development must be grounded in responsible design and governance to enhance human autonomy and well-being.