Getting used to wonderful incidents is a disaster. For instance one hears about the miracles of our Prophet (saas), his eyes get filled with tears, he feels astonished. And then familiarity swallows him in an instant. People have a tendency towards getting used to everything. One needs to resist that.
Getting used to important facts and wonders is very dangerous. That is one of the points a Muslim should work on the most. For instance one studies the structure of the cell and feels out of breath. But an intense wave of familiarity at the back of his mind would constantly suck that knowledge. It constantly suppresses that amazing information.