mysql – Under what circumstances will the transaction fail to see itselfs submission?

I use mysql to update by primary key. there is two transaction start at same time to operate same line。but one fail to see itselfs submission,audit_status is not 3.

START TRANSACTION;
/ip=...64*/
update table
set audit_status = 3
where id = 10001;

/ip=...64*/
select audit_status
from table
where id = 10001;
COMMIT;

SELECT @@transaction_isolation;
REPEATABLE-READ