Lin Wu had realized that at the 20 meter mark the increase in power he got had reached a plateau. Even if he expanded it beyond this, there would be no more gains. The main point of having a larger Dao shell was to have a better chance at accommodating a Dao Embryo.
The stronger Dao Embryo's were often bigger in size and could grow further in the Dao Treading realm too. If one didn't have a sufficiently large Dao Shell, they wouldn't be able to unearth the true potential of their Dao Embryo thereby making them weaker than their peers.
Such was the common understanding among the cultivators in many worlds.
Lin Wu thought so too and went for the maximum expansion of the Dao shell. Even when he felt the diminishing growth rate at the ten meter mark he didn't stop. He wanted to see if he could exceed the limits and find something new.
