Last night, I finished building LEGO City 60312, police car with my 5 years old son. After completion, we ended up with 9 leftover pieces. I rechecked the instruction manual several times and couldn't find any missing steps or unused attachment points that may explain this. In fact, on the last page of the instruction manual, there is a list and quantity of all pieces and the extra pieces are not reflected in the list at all.

Is this typical to have multiple spare pieces, especially for a tiny set or does this indicates an issue with the inventory or the build. Maybe I am just overthinking this.

Anyone have an idea what those extra pieces