There are many written standards for German Shepherd dogs. These standards change over time. Interpretation of standards and goals of a breeder shape future generations. Many breeders don’t think of how the standard applies to their own dogs, and not everyone has a good eye for structure and movement, or any goal at all.
When talking with potential German Shepherd owners I frequently hear, “I’m not looking for a show dog.” or, “I only want a pet.” In some way perhaps they are trying to communicate that budget may be an issue. Although I can totally understand needing to stay within one’s means, one should not cut corners or underestimate the value in buying a well bred dog.   Good breeding has the greatest potential for good health, temperament and longevity.
One way a breeder can ensure their dogs are worth breeding is to show them. Work them. Get opinions from experts about the quality and workability of their dogs. The average pet home doesn’t care that our dogs took 1st and 2nd in national competitions in 2017. And 1st and 2nd in Regional competitions in 2018.  The average pet owner doesn’t care that we have generations of dogs reaching the 13 club (German Shepherd Dog Club of America’s way of recognizing extreme longevity). The average pet owner doesn’t care that we screen for every possible genetic health clearance. We care.
When looking for a pup why do these things even matter? When a dog is bred to a standard, the breeder is ensuring not just a good structure, but also a solid temperament. Bad structure can lead to pain. Pain can bring temperament issues. It ALL matters.
Some of these diagrams, borrowed from the German Shepherd Dog Club of America’s website, may help in evaluating structure: