- Losing reference to head: Save head reference before traversal. Moving the head pointer without backup loses the list.
- Not handling edge cases: Empty list, single node, two nodes often need special handling.
Use dummy nodes to simplify.
- Null pointer errors: Always check if a pointer is null before accessing its next field.
- Wrong termination in cycle detection: Fast pointer and fast.next both must be non-null before moving fast two steps.