All of them LOL
In terms of the smaller models, what killed Pontiac and almost Chevy ( Lets remember the final verdict on "Government Motors" is still out, and not looking good by a long shot) Neither could produce a small car with style, price, and dependability that wasnt perceived as an "economy car".
In terms of the Bonneville (full size) price was a huge issue. Models? In early 2006 I decided the 2005 LaCrosse I bought wasnt big enough for me or my needs. I was looking at the Camry, Galant, and especially the Avalon. To be frank, I would never have considered my GXP at the MSRP of $39,800. What sealed the Bonne deal was getting it showroom fresh for $10,500 off and the 7/70 GMPP added. The economy boomed late 80'*/early90'*. And the SUV and big Truck came and went. Detroit saw nice profits, and gave it all away to vendors and employees in a pace that couldnt be maintained even without the economy falling and the "big" trend falling flat. Lets consider the fact Toyota and Honda remained solvent and paid dividends even while retooling and adapting. GM still doesnt get it, and I dont believe they can become solvent again, and wonder how far the Government will extend throwing more money on a fire that wont go out.