f a person does not resolve a stage successfully, it may hinder their ability to deal with later stages. For example, the person who does not develop a sense of trust (Erikson's first stage) may find it challenging as an adult to form a positive intimate relationship (Erikson's sixth stage). Or an individual who does not develop a clear sense of purpose and identity (Erikson's fifth stage) may become self-absorbed and stagnate rather than work toward the betterment of others (Erikson's seventh stage)
When a person does not complete one stage, for example, if as a baby you do not learn how to trust, then as an adult they might have a difficult time trusting people. According to Erikson, each stage builds on the one before. It is like a domino effect: if you don’t learn to trust at an early stage, then all the dominoes will fall down. When you do not learn how to trust as a baby, it could set off a chain of reactions that make later stages feel more challenging. Just as knocking over the first domino causes the rest to fall, struggling in an early stage can affect those that come after.