Why is there a 128A Compliance hearing when a Will is probated? What are you supposed to comply with?

I am in Texas. I know I am complying state law but more specifically, what part of the probate process must I show that I followed through with? I filed a Certificate of Compliance (with copy of attached Notices with the Order issuing Letters Testamentary? Does that not suffice? http://bit.ly/pRY2eh