Two Birds With One Stone.

In addition to the law comprehension requirement, all the concepts must not antagonize each other and they must also improve each other. The effect of each seed of power must have a positive effect on the others. It is in this way that they can be fused after the laws that make them up have been comprehended. The seeds of power that don't match the others will be lost during the breakthrough to become Origin god. 

The other disadvantage of this process of breakthrough is that Supreme beasts will be the weakest Sovereigns of law. Their chances of passing the tribulation are abysmal because they did so through the process of step-by-step strengthening by the universe through the lord of law and finally sovereign of law. They will even be weaker than titans of law that became false sovereigns.