This is the paint you apply initially to the figures major feature areas to identify colour zones. For example at this point you would paint the legs, boots, body and clothing. It does not matter if you wipe over features such as belt buckles patches, sword hilts, etc. These are all fine details that can be done later (the fun bit). So brown trousers, blue tunic, black boots, grey hair and flesh coloured err flesh!
Your figure should now look at least look like everything is the right colour for the right place. The detail applied on top of this crude layer are what make the figure stand out.