Could you explain why for the following PostgreSQL function:

CREATE FUNCTION components.remove_empty_gaps()
    RETURNS TRIGGER
    LANGUAGE plpgsql
    AS $$
    DECLARE
      current_page_id UUID;
      deleted_row_start INT;
      deleted_row_end INT;
      row_span INT;
    BEGIN
      current_page_id := OLD.page_id;
    
      SELECT row_start, row_end INTO deleted_row_start, deleted_row_end
      FROM components.component_position
      WHERE component_id = OLD.id;
    
      row_span := deleted_row_end - deleted_row_start + 1;

      IF OLD.type = 'header' OR OLD.type = 'section' THEN
        UPDATE components.component_position cp
        SET row_start = row_start - row_span,
            row_end = row_end - row_span
        FROM components.component c
        WHERE cp.row_start > deleted_row_end
        AND cp.component_id = c.id
        AND c.page_id = current_page_id
        AND c.type != 'footer';
      END IF;
      
      RETURN OLD;
    END;
    $$;

These two statements behave differently?

    CREATE TRIGGER remove_empty_gaps
    BEFORE DELETE ON components.component
    FOR EACH STATEMENT
    EXECUTE FUNCTION components.remove_empty_gaps();

    CREATE TRIGGER remove_empty_gaps
    BEFORE DELETE ON components.component
    FOR EACH ROW
    EXECUTE FUNCTION components.remove_empty_gaps();

For example, given this data in the component_position table:

{
"component_position": [
    {
        "component_id" : "39dadec0-24b7-40cd-9fb9-41cbc17a2460",
        "row_start" : 1,
        "col_start" : 1,
        "row_end" : 2,
        "col_end" : 13,
        "row_end_span" : 0,
        "col_end_span" : 0
    },
    {
        "component_id" : "54718411-dfb1-40a3-ba01-8703e435ed33",
        "row_start" : 3,
        "col_start" : 1,
        "row_end" : 4,
        "col_end" : 13,
        "row_end_span" : 0,
        "col_end_span" : 0
    },
    {
        "component_id" : "857df909-fb40-4d24-86e6-992110ee12df",
        "row_start" : 5,
        "col_start" : 1,
        "row_end" : 6,
        "col_end" : 13,
        "row_end_span" : 0,
        "col_end_span" : 0
    },
    {
        "component_id" : "7a00db94-53f2-41df-8ca7-e0b9764e5996",
        "row_start" : 7,
        "col_start" : 1,
        "row_end" : 8,
        "col_end" : 13,
        "row_end_span" : 0,
        "col_end_span" : 0
    }
]}

When using the FOR EACH ROW and deleting component 54718411-dfb1-40a3-ba01-8703e435ed33, the unexepcted output would look like this:

{
"component_position": [
    {
        "component_id" : "39dadec0-24b7-40cd-9fb9-41cbc17a2460",
        "row_start" : 1,
        "col_start" : 1,
        "row_end" : 2,
        "col_end" : 13,
        "row_end_span" : 0,
        "col_end_span" : 0
    },
    {
        "component_id" : "857df909-fb40-4d24-86e6-992110ee12df",
        "row_start" : 3,
        "col_start" : 1,
        "row_end" : 4,
        "col_end" : 13,
        "row_end_span" : 0,
        "col_end_span" : 0
    },
    {
        "component_id" : "7a00db94-53f2-41df-8ca7-e0b9764e5996",
        "row_start" : 3,
        "col_start" : 1,
        "row_end" : 4,
        "col_end" : 13,
        "row_end_span" : 0,
        "col_end_span" : 0
    }
]}

While the FOR EACH STATEMENT with deleting 54718411-dfb1-40a3-ba01-8703e435ed33, the output is correct with the proper shifting:

{
"component_position": [
    {
        "component_id" : "39dadec0-24b7-40cd-9fb9-41cbc17a2460",
        "row_start" : 1,
        "col_start" : 1,
        "row_end" : 2,
        "col_end" : 13,
        "row_end_span" : 0,
        "col_end_span" : 0
    },
    {
        "component_id" : "857df909-fb40-4d24-86e6-992110ee12df",
        "row_start" : 3,
        "col_start" : 1,
        "row_end" : 4,
        "col_end" : 13,
        "row_end_span" : 0,
        "col_end_span" : 0
    },
    {
        "component_id" : "7a00db94-53f2-41df-8ca7-e0b9764e5996",
        "row_start" : 5,
        "col_start" : 1,
        "row_end" : 6,
        "col_end" : 13,
        "row_end_span" : 0,
        "col_end_span" : 0
    }
]}

I thought in this case FOR EACH ROW should give the exact same result as FOR EACH STATEMENT considering I only delete a single row.