Why is it harder to predict someones phenotype than genotype?

Predicting someone's phenotype is more challenging than predicting their genotype because phenotype is influenced by both genetic factors and environmental conditions. While genotype refers to the specific genetic makeup, phenotype encompasses a wide range of observable traits, such as appearance, behavior, and health, which can be affected by factors like diet, lifestyle, and environmental exposures. Additionally, many traits are polygenic and may exhibit variable expressivity and incomplete penetrance, further complicating predictions based solely on genotype.