Account Generator not Generating Some GL Code Combinatins

Account generator is not generating some GL Code Combinations eventhough the source values are populated on the Asset Categories or Book Controls form.  It was my understanding that when the "Generate Accounts" process is run for the first time, Account Generator generates ALL GL Code Combinations so long as the Book Controls form and Categories form contains the necessary source values.  For example, Bonus Expense and Bonus Reserve fields are populated on Categories form.  Generate Accounts concurrent process run without errors but FA_ DISTRIBUTION_ACCOUNTS table has no ccid for these functions.  Why are these code combination not being generated?  Also happening sometimes for CIP COST and CIP CLEARING.