We can't move mountains unless God wants those mountains moved.

Jesus was talking to his disciples about faith to do the work that he called them to do. Jesus never performed self-serving miracles. The disciples didn't look at being able to get whatever they asked for in prayer as a way to satisfy their own selfish desires.

What Jesus said about asking in faith isn't a guarantee. Or my wife wouldn't have died when she was 30. And our two children wouldn't have been stillborn.