If you try and use the same method of training each and every day to raise your strength level, you will eventually reach a point where you are able to go no further. You must incorporate new exercises that are also more difficult in order to raise your standards. You cannot simply bench, squat, and deadlift. You have to do more than this.
Perhaps the best example is going to be Lamar Grant. He held the world record for bench and deadlift at the same time. There are plenty of men who hold records for just the deadlift, or just the bench, but there is no way that they could even make the top 10 of the other list. This is because they have limited themselves by body structure as well as by muscle groups.
The conjugate system originated from the Dynamo Club within the former Soviet Union. They had Olympic lifters that were using a system of 20 to 45 special exercises and these were grouped per workout so that they could rotate as needed. They got stronger and were able to work within multiple areas of competition – and this is what the conjugate method is going to do for you.