Pin access
Beginner
Whether wires can actually reach each connection point on a part without breaking a rule.
Novice
Whether the wiring step can connect a wire to each of a cell’s pins (its input and output contact points) without breaking a manufacturing rule. Tightly packed cells can block each other’s pins.
Expert
At advanced nodes, tiny low-metal pins, few tracks per cell and complex via rules mean two legal neighbors can still leave a pin unreachable. Fixes include padding, pin-access-aware detailed placement, and placement refinement during routing.