Is there a reason why they always stab that one spot on the bull in bullfighting?

As mentioned, the colored spears aren’t mean to kill, and the matador’s sword thrust is intended to give a quick, clean kill of the bull (without a quick, clean kill of the Matador).
It’s like that old Gary Larsen cartoon – “We should write that spot down.”

My brother has been in Barcelona all week and I asked about bullfighting. He told me it has been banned. I hadn’t heard and was surprised. For me Spain has always been about bullfighting and the eponymous rice.

Joe traveled to Spain and wandered into a Madrid restaurant one night for a late dinner.

He ordered the house specialty and was brought a plate with potatoes, corn, and two large meaty objects. “What’s this?” Joe asked.

“Cojones, senor,” the waiter replied.

“But, what are cojones?” Joe asked.

“Cojones,” the waiter explained, “are the testicles of the bull who lost at the arena this afternoon.”

At first Joe was disgusted; but being the adventurous type, he decided to try this local delicacy. To Joe’s amazement, it was quite delicious. In fact, it was so good, Joe decided to return the next night and order it again.

This time, the waiter brought out the plate, but the meaty objects were much smaller.

“What’s this?” Joe asked the waiter.

“Cojones, senor,” the waiter replied.

“No, no,” Joe objected, “I had cojones yesterday and they were much bigger than these.”

“Senor,” the waiter explained, "the bull does not always lose