What causes holes to tear in the esophagus?

Multiple causes: This can be caused by retching(forceful vomiting), foreign bodies(bones, etc), ulcerations, cancer, etc. The most common cause is forceful retching.

Many causes: There are many possibilities. Anywhere from ingesting some foods, bones, pointy objects, severe vomiting, etc.

Rare : Esophageal perforations are not common. It can occur in the setting of excessive vomiting or retching. Also possible with a prolonged food impaction or even severe pill esophagitis.