Shows are scored based on the primary, secondary, and tertiary stats for the discipline you are showing in. The primary stat used in the discipline counts the most for a show score with secondary and tertiary counting a bit less. Also important for showing, is a horse close to its breed standard. Breed standard has some influence on how well your horse scores in a show. So, horses with mostly poors or fairs may not excel as discipline show horses.
What Makes a Good Show Horse?
A good show horse will have as close to excellent BS as possible. A horse with mostly “Poor” for its breed standards will have more reductions in shows than a horse with mostly “Excellent” BS.