  A new model is proposed in which typical galaxies form most of their stellar
mass in a phase with an intrinsically red stellar population. In the standard
picture, galaxies with intrinsically red stellar populations are believed to
have old stellar populations, so that only galaxies with blue stellar
populations have significant star formation, and subsequent changes to the
stellar population come from predominantly from aging and merging populations
which have already formed. However, several observational puzzles have
developed which are difficult to reconcile with this standard scenario. The
most massive blue star-forming galaxies, presumed to be at the end of their
stellar mass growth, are $\sim 1$ dex less massive, have a $\sim 1$ dex lower
$M_*/M_{BH}$ ratio, and have a bottom-lighter IMF than local quiescent
galaxies. Here, a new solution is proposed: at low temperature and high
metallicity, galaxies can continue to form stars efficiently without being able
to form O and B stars. These red star-forming galaxies would have many of the
same properties of the population currently described as post-starburst
galaxies, allowing a new interpretation of their origin. Finally, additional
falsifiable observational predictions of this model are also discussed.
