General Motors' (NYSE: GM) GMC had an ad on last night's Super Bowl for the first time in years. It cost something in the neighborhood of $5 million to broadcast, and if you're a GM stockholder, you might want to ask: why did GM waste so much money?

The ad (you can see it below) is a spare, black and white cartoon of a human figure rolling a large boulder up a hill. The figure works immensely hard, pushing the rock for over 45 seconds -- an eternity in Super Bowl ad time. Finally, he gets the rock to the peak of the mountain. Fade to a white GMC Yukon hybrid, which, according to the ad, gets 50% better mileage than a regular Yukon.

There are a number of problems with the ad. First, it brings to mind Sisyphus, who in Greek mythology is condemned to push a boulder up a hill and then watch it roll back down, over and over again, for all eternity. In other words, to do something that is both back-breaking and utterly pointless. And this makes me wonder, what is the point of squeezing a few more miles per gallon from a gigantic, wasteful truck? The hybrid Yukon gets a paltry 21 mpg -- hardly worth celebrating. A better idea would be to just get rid of the thing altogether. Stop rolling that boulder up the hill! GM would be much better off if it concentrated on making smart, fuel efficient vehicles rather than fighting gravity by trying to make a huge truck perform like a Toyota Prius.

The other problem with the ad is that it is slow and offers very little by way of persuasion, either in terms of zany entertainment or sober fact. I'm not alone in this conclusion, since the ad is getting consistently negative reviews. Students at Northwestern rated the ad among the worst from the 2008 Super Bowl for both marketing and entertainment purposes.

You can take a look for yourself: