Cecil makes mistakes because he's painfully aware of how powerless he is in the grand scheme of things and that pushes him to take control of everything and causes problems while trying to preemptively take control of the what-ifs that could happen
Thaedus makes mistakes because despite being more moral than most Viltrumites, he's still arrogant about his own power and causes problems because his assumption that he's always in control in the moment made him ignore potential backfire
Cecil's flaws are born from the paranoia of things he cannot control
Thaedus's flaws are born from the hubris of not recognizing that there are always things out of your control
