by Norberg & Maeder (2000) and Behrend & Maeder (2001) was to increase the accretion rate as the mass of the star grows. There is a region of the mass-luminosity plane where spherical accretion rates can grow and keep above that needed to overcome radiation pressure on dust in the cocoon, but below the Eddington limit due to radiation pressure on electrons in the stellar atmosphere. They attempted to put this on a physical basis by using the observed relation between outflow rates and bolometric luminosity (e.g. Churchwell 1998) and then making the accretion rate a fraction of the outflow rate. This invokes the often found result from outflow models that the outflow rate is a fixed fraction of the accretion rate. Their prescription gave very high accretion rates ($\sim$10$^{-2}$) at the upper end of the mass range. However, the observed outflow rate versus luminosity relation is likely to be severely affected by selection effects for massive objects. Firstly, the objects observed are likely to be at a wide range of evolutionary stages. More importantly, Ridge & Moore (2001) showed that when a constant distance sample is studied there is much less of a correlation between outflow rate and luminosity 