So

Lizards.

I hate them.

Reason Number One:
Lizards are not intelligent creatures.  They are, in fact, extremely stupid.
Proof:
I am attempting to clean the pool and I go to reach for the pool vacuum.  The lizard then proceeds to flee my presence by running directly into the pool screen over and over and over.  Evidence: affirmative.

Reason Number Two:
Lizards have no sense of personal space.
Proof:
I am letting my cat outside via the front door.  I am clearly inside and in no way out of the door.  Splat.  Lizard on my foot.  Evidence: affirmative.

Reason Number Three:
Lizards are repulsive.
Proof:
I am walking out the door and I see a lizard's tail detached from its body, still wiggling.  I am repulsed.  Evidence: affirmative.

Thus, I cannot abide the presence of lizards.