We discuss the droplet contact angle as the key parameter influencing the morphology and the related crystal phase of vapor-liquid-solid III-V nanowires. In particular, we show that twinning superlattice Te-doped GaAs nanowires are formed only when the droplet contact angle is above 130°, and that pure wurtzite sections in self-catalyzed GaP nanowires are obtained in the stage of Ga droplet consumption when the contact angle is within the range from 95° to 105°.