There is so much that goes on behind the scenes with a horse and a stable that doesn’t show up in the past performances.
For instance, when a jockey rides a certain horse in a race after
previously riding another one, it’s easy to assume he or she liked the
one better than the other. A handicapper might use that assumption in
making a bet. And while it could be accurate, often there’s another
explanation that has nothing to do with the perceived ability levels of
the two horses.