CONVERT() not converting properly

I have a table example:

id  -- score
1   -- 5.66678
2   -- 11.598
3 -- 12.2
4 -- 11.598
5 -- 2.577777

score is set as a VARCHAR currently.
id is an integer

My simple MySQL query:

SELECT *
FROM `mysql_table`
ORDER BY CONVERT( score, DECIMAL ) DESC

For some reason it pulls it something similar to this:

id  -- score
2   -- 11.598
3 -- 12.2
4 -- 11.598
1   -- 5.66678
5 -- 2.577777

12.2 is stuck between the two 11.598’s. Is there a reason for this? Am I doing something wrong?

please run this and show what it produces…


SELECT *
     , CONVERT( score, DECIMAL ) AS sortby
  FROM `mysql_table`
ORDER 
    BY CONVERT( score, DECIMAL ) DESC