  Star clusters larger than $\sim 10^{3}$ $M_\odot$ contain multiple hot stars
that launch fast stellar winds. The integrated kinetic energy carried by these
winds is comparable to that delivered by supernova explosions, suggesting that
at early times winds could be an important form of feedback on the surrounding
cold material from which the star cluster formed. However, the interaction of
these winds with the surrounding clumpy, turbulent, cold gas is complex and
poorly understood. Here we investigate this problem via an accounting exercise:
we use empirically determined properties of four well-studied massive star
clusters to determine where the energy injected by stellar winds ultimately
ends up. We consider a range of kinetic energy loss channels, including
radiative cooling, mechanical work on the cold interstellar medium, thermal
conduction, heating of dust via collisions by the hot gas, and bulk advection
of thermal energy by the hot gas. We show that, for at least some of the
clusters, none of these channels can account for more than a small fraction of
the injected energy. We suggest that turbulent mixing at the hot-cold interface
or physical leakage of the hot gas from the HII region can efficiently remove
the kinetic energy injected by the massive stars in young star clusters. Even
for the clusters where we are able to account for all the injected kinetic
energy, we show that our accounting sets strong constraints on the importance
of stellar winds as a mechanism for feedback on the cold interstellar medium.
