Jesus responded (Matt.20:20-24) by saying that she didn’t know what she was asking.
“Can they drink the cup that I going to drink?” (i.e. referring to his death). Salome’s request was born out of pride and selfishness.
Did her two sons deserve thrones? Thrones are not given away, you have to earn them. Salome had forgotten the true cost of reward. She did not realize that suffering comes before reward. There is no crown without a cross. There is no wearing of a crown without the drinking of the cup of suffering. Even the Lord Jesus Christ himself did not return to the throne of heaven except by way of the cross.
Sometimes we can be so selfish in our desires. Salome’s request for her two sons was a selfish, earthly, proud request. She did not realize the price that her two sons would have to pay. Remembers James, he was martyred and John was exiled before they went home to glory. Salome was at the place of correction standing at the cross, realizing what it cost Jesus, the Son of God, to give up. Jesus gave up the glory of heaven and became a servant for us by giving his life for us.