The barren fig tree is cursed. This passage shows that Jesus does not just warn of Judgement, but actually does really judge those who are in ongoing rebellion against him.

This is what was prophesied in Jeremiah 8:13 and other places, warned of in Luke 13:1-9 and Hebrews 10:30

Mark 11:12 The next day when they went out from Bethany, he was hungry. 13 Seeing in the distance a fig tree with leaves, he went to find out if there was anything on it. When he came to it, he found nothing but leaves; for it was not the season for figs. 14 He said to it, “May no one ever eat fruit from you again!” And his disciples heard it.