1. Oral Stage (0-1 year): During this stage, the primary focus is on the mouth and the pleasure derived from sucking, biting, and chewing. If this stage is not successfully completed, it can lead to issues with dependency, overeating, smoking, or other oral fixations in adulthood.
2. Anal Stage (1-3 years): This stage is focused on toilet training and the pleasure derived from controlling and expelling feces. If this stage is not successfully completed, it can lead to issues with control, orderliness, and cleanliness in adulthood, or conversely, rebellion and messiness.
3. Phallic Stage (3-6 years): During this stage, children become aware of their own bodies and develop a sexual attraction to the opposite-sex parent (Oedipus complex for boys, Electra complex for girls). If this stage is not successfully completed, it can lead to issues with gender identity, sexual orientation, and relationships in adulthood.
4. Latency Stage (6-12 years): This stage is characterized by a focus on developing social and cognitive skills, with sexual impulses being repressed. If this stage is not successfully completed, it can lead to difficulties forming friendships, low self-esteem, and problems with academic or career success.
5. Genital Stage (puberty onwards): This stage marks the beginning of adult sexuality and the ability to form mature, intimate relationships. If previous stages have not been successfully completed, it can lead to difficulties with intimacy, commitment, and sexual satisfaction in adulthood.