SQL Job Fails After 4 Failed Exec() Calls

I am running the code below in a sql job. Exec (@SQL) errors every time but after 4 failures the job fails instead of trying @MaxRetries times. Any idea on why this is happening?
Set @RetryCounter = 0
WHILE (@RetryCounter < @MaxRetries)
Begin
SELECT @error_value = 0
Exec (@SQL)
SELECT @error_value = @@ERROR
If @error_value = 0
Set @RetryCounter = @MaxRetries
Else
Begin
WAITFOR DELAY '00:05:00'
Set @RetryCounter = @RetryCounter + 1
End
End