Zeb forgets that his legs are short and that he is - in effect - a small dog.
In his mind, he is a grehound/doberman/shepherd cross...
In reality, he is a corgi - a small corgi.
Zeb is a pretty fast runner and an excellent herder.
In his mind he is faster Secretariat.
In reality, he's not that fast.
Zeb is not fast enough to catch a deer.
You think he would have figured that out by now...
Today he chased one across the yard and into the woods.
He returned 20 minutes later -- sans deer.
Maybe it's the chase he likes.
Maybe it's the exercise -- nah -- he is currently curled up, happily snoring in his crate.
He's probably dreaming about catching that deer.