Replication between master and slave is running, but still there is a one row difference in a few tables when checked with pt-table-checksum

This is the master status

mysql> show master status;
+------------------+-----------+--------------+------------------+-------------------+
| File             | Position  | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+-----------+--------------+------------------+-------------------+
| mysql-bin.000039 | 796685393 |              |                  |                   |
+------------------+-----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

This is the slave status.

mysql> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: ---------
                  Master_User: secondary
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000039
          Read_Master_Log_Pos: 796683447
               Relay_Log_File: ---------------
                Relay_Log_Pos: 488478421
        Relay_Master_Log_File: mysql-bin.000039
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB:
          Replicate_Ignore_DB:
           Replicate_Do_Table:
       Replicate_Ignore_Table:
      Replicate_Wild_Do_Table:
  Replicate_Wild_Ignore_Table:
                   Last_Errno: 0
                   Last_Error:
                 Skip_Counter: 0
          Exec_Master_Log_Pos: 796682447
              Relay_Log_Space: 488478639
              Until_Condition: None
               Until_Log_File:
                Until_Log_Pos: 0
           Master_SSL_Allowed: No
           Master_SSL_CA_File:
           Master_SSL_CA_Path:
              Master_SSL_Cert:
            Master_SSL_Cipher:
               Master_SSL_Key:
        Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno: 0
                Last_IO_Error:
               Last_SQL_Errno: 0
               Last_SQL_Error:
  Replicate_Ignore_Server_Ids:
             Master_Server_Id: 1
                  Master_UUID: 677f82ac-de9f-11ea-85db-fa163ee8b7b4
             Master_Info_File: /var/lib/mysql/master.info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
           Master_Retry_Count: 86400
                  Master_Bind:
      Last_IO_Error_Timestamp:
     Last_SQL_Error_Timestamp:
               Master_SSL_Crl:
           Master_SSL_Crlpath:
           Retrieved_Gtid_Set:
            Executed_Gtid_Set:
                Auto_Position: 0
         Replicate_Rewrite_DB:
                 Channel_Name:
           Master_TLS_Version:
1 row in set (0.00 sec)

Seconds_Behind_master is 0, there is a difference in binlog positions. Out of 35 tables in the database, 4 have a one-row difference in the pt-table-checksum result. I want to write a script to see if the replication is working and if there is no data drift. Is having 1 difference ok? If not, how can I reach the ideal 0 difference?