Through hole components should set the shape of Pin 1 to
Rounded Rectangle, and all other pads to either
This aids in orienting the component during placement and also for locating Pin 1 for circuit troubleshooting.
For rounded rectangle pads the corner size should be 25% with a maximum radius of 0.25mm.
Pad shape can be adjusted in the Pad Properties dialog:
Non polarized parts (such as THT resistors) should not set the shape of Pin 1 to Rectangular. For these (non polarized) footprints, all pad shapes should be consistent.