We show that the spherical, polytropic stellar winds are stable to all adiabatic fluctuations in the sense of absolute and convective stabilities. It is also shown that the neutrally stable sound waves driven by stellar turbulence or nonradial pulsations are trapped and become much enhanced near both the wind-flow base and the sonic resonance. They can exert great wave pressure at both locations, which are known to be critical in determining wind strength. This finding is strongly suggestive of a possible intimate connection between stellar turbulence and/or pulsations and stellar wind flux. In addition, a scenario for the appearance of large-amplitude waves riding on the winds at great, and hence observable, distances is given in the above context.