Why do the Wolffian ducts usually deteriorate in female fetal development?

In human embryology, the Wolffian duct system deteriorates in female fetuses primarily due to the absence of androgenic stimulation.1

During fetal development, the presence of testosterone is required to stimulate the Wolffian ducts to differentiate into male reproductive structures, such as the ductus deferens and seminal vesicles. In a normal female fetus, these androgenic effects do not occur; consequently, the Wolffian ducts lack the necessary hormonal signals to persist and instead regress.1

Conversely, the Müllerian duct system, which serves as the precursor for female reproductive organs, develops in the absence of Müllerian inhibiting hormone—a substance secreted only by the testes of XY fetuses. Therefore, female development proceeds by default when these specific masculinizing influences are absent.1