I think we forget that
Moses was human and had common frailties like the rest of humanity. He
stuttered and he whined a lot. In fact, he complained to God that he was
ill-equipped to speak to Pharaoh. But he did have the wisdom to know
that if he were to speak to Pharaoh, it would only be with God's help.
So when we are called upon to make miracles, we can't. But God can
make miracles through us—even with whiners like Moses.