Eren wanted to take the easy and safe way out by prolonging the battle.
Aleph wished him to do the opposite. He wanted Eren to face Arto head-on and not run away from a fight. He wanted Eren to consciously make an effort to break into the Awakened rank, which was supposed to be a significant hurdle in a ranker's life.
Aleph pulled into a near-stagnant world and explained further.
"I wouldn't have said this earlier, Eren. But you have turned this task into a suicide mission for yourself. There were several ways you could have obtained the warehouse's resources without getting killed in the process. But what's done is done.
