What does Jesus mean when he asks his disciples ''Do you not yet perceive?''?

Matthew 16:9–10 (ESV)

9 Do you not yet perceive? Do you not remember the five loaves for the five thousand, and how many baskets you gathered?

In short

Jesus’ rebuke of his disciples’ little faith (Matthew 16:8) is seen in his asking right afterward in Matthew 16:9–10: Do you not perceive? Do you not remember the five loaves for the five thousand, and how many baskets you gathered? They still lack a faith that expects everything from him, even though they knew how much food was left over—food they had neither bought nor stored. Jesus reminds them not mainly of the miracle of feeding the multitudes, but of all that remained for the disciples themselves. In their service to him, they had always received their literal daily bread (Matthew 6:11)

They ought to have known that even when that bread was lacking, Jesus would take care of them (see also Mark 6:52), and he had already twice provided for the crowds. The phrase still not shows his frustration.

That Jesus is reproaching his disciples when he calls them of little faith (Matthew 16:8) is evident from the question he poses immediately thereafter in Matthew 16:9–10: Do you not perceive? Do you not remember the five loaves for the five thousand, and how many baskets you gathered? The faith that truly expects everything from him is still lacking—even though they could recall the overflowing baskets they had carried away after the feeding of the five thousand, food they had neither bought nor stored. Once again, Jesus reminds them not primarily of the miracle of feeding the multitudes, but of the abundance that remained for the disciples themselves. In their service to him, they had always received their literal daily bread (Matthew 6:11).¹

They ought to have known or perceived that even when that bread was lacking, it was no serious matter, as Jesus would take care of them (see also Mark 6:52). And the apostles should have known this, for Jesus had already twice provided for the crowds. The phrase still not expresses his impatience. They had forgotten his miracles and therefore failed to learn any lesson from them.²