You really need only a single ROW_NUMBER function:

SELECT

MAX(CASE WHEN row_num % 3 = 0 THEN LotNo ELSE '' END) AS Lot1,

MAX(CASE WHEN row_num % 3 = 1 THEN LotNo ELSE '' END) AS Lot2,

MAX(CASE WHEN row_num % 3 = 2 THEN LotNo ELSE '' END) AS Lot3

FROM (

SELECT LotNo, ROW_NUMBER() OVER(ORDER BY LotNo) + 2 AS row_num

FROM LotNo

) AS derived

GROUP BY row_num / 3