Pride.
Oh, pride!
It was the deep and conscious satisfaction of oneself, something that experts achieving grand realms have too much of in abundance.
It is pride that causes the downfall of many beings, it is pride that is the cause of great experts becoming careless as all of sudden...they fall from their high pedestals and into an extremely painful experience!
The Half-a-Step Great Sage has a true body in the Primordial Cosmos as he was extremely powerful, and he had such confidence in himself and the Dao of Destiny that in the last few seconds of the Final War of the Dark Universe...he pridefully closed his eyes as he awaited to experience Ruination from the hands of the Master of Ruination.
He waited for what he was destined for...but it would never arrive!