Final answer:
The incorrect statement about self-concept development is that it is not influenced by cultural factors; in reality, cultural factors play a significant role in shaping self-concept.
Step-by-step explanation:
The incorrect statement pertaining to self-concept development is: "Self-concept development is not influenced by cultural factors." This statement is incorrect because self-concept development is indeed significantly influenced by cultural factors, as well as by social interactions, self-reflection, and self-evaluation. The development of self-concept is a complex process that begins in early childhood and continues throughout a person's life, deeply intertwined with socialization and influenced by various stages of psychosocial development, as proposed by theorists like Erik Erikson.