Bob Lutz, in an interview with Advertising Age, stated the obvious: GM has too many brands.

Actually, he stated: "It's really much better to have fewer brands, do it well and then market the hell out of them."  In the piece, Lutz made it official: GM is going to axe a number of divisions, which now appears to be widening in scope.  A number of nameplates will, obviously be joining them. 

Lutz went into specifics about the problem of rebadging, singling out the Saturn Aura.  While the Malibu has enjoyed fairly strong sales for the year at 161,000 so far, the Aura has managed a measley 56,000.  As GM's vice-chair put it: "Three years later, people are still saying 'What's an Aura?'  Lutz blamed the failure to revive Saturn on too few marketing dollars.  There are simply too many company vehicles sharing the same architecture, competing for the same buyers, and draining limited developmental and advertising resources.

At least a top exec openly admitted it: albeit 20 years late.