Complex sentence: Dog food commercials frequently ended with a dog actually not enjoying the product, but no matter how good the food looks on camera, or how good its story sounds, the commercial is not a success until the dog actually eats the dog food.
Split into simpler sentences: Dog food commercials frequently ended with a dog actually not eating the product. Thus, no matter how good the food looks on camera, or how good its story sounds, the commercial is not a success until the dog actually eats the dog food.