Adam Clarke on Jonah 4:1

But it displeased Jonah exceedingly - This hasty, and indeed inconsiderate prophet, was vexed because his prediction was not fulfilled. He had more respect to his high sense of his own honor than he had to the goodness and mercy of God. He appeared to care little whether six hundred and twenty thousand persons were destroyed or not, so he might not pass for a deceiver, or one that denounced a falsity.

And he was very angry - Because the prediction was not literally fulfilled; for he totally lost sight of the condition.