Why do the leads of some resistor have holes?

Is it to:

• Run a wire through it before soldering? If so, what is the best technique?
• Run a tiny screw through it for connecting a tiny lug?
• provide a barrier against conductive heat transfer between the body and the tip (by both the hole and the flattening, soldering the tip only)?

Example (the undeformed part of lead diameter is 2.5mm in his case; the hole diameter is 1.8mm):

Why do the leads of some resistors have holes?

Is it to:

• Run a wire through it before soldering? If so, what is the best technique?
• Run a tiny screw through it for connecting a tiny lug?
• Provide a barrier against conductive heat transfer between the body and the tip (by both the hole and the flattening, soldering the tip only)?

Example (the undeformed part of lead diameter is 2.5mm in his case; the hole diameter is 1.8mm):