Mark 6:4,5,6 God is sometimes wondering, even today, just as Jesus did, thousands of years ago, about our lack of faith, in him, and his Word and promises.
In Mark 6:5 Jesus was amazed, about their lack of faith. Jesus wanted to do miracles in that place, just as he wants to do them everywhere and also today. But those people in Mark 6, pulled the handbrake of their faith, and placed a Stop sign, in front of Jesus, to confirm their unbelief. They did not believe him, because they knew him, his parents, his relatives, his brothers and sisters, and they knew the man Jesus, but completely omitted Jesus the Almighty God, the Creator of everything.
And so Jesus choose not to tolerate their unbelief, by not doing many miracles there.
You see, God honors our faith in him, and he will always support a genuine faith in his Word, by even doing miracles, signs and wonders, if necessary, but he can not, and will not tolerate our doubt and unbelief, because, if God answered our prayer full with unbelief, when we ask for something from him, that means he will stimulate us to continue in our life, praying prayers full with unbelief.
We will just think to ourselves, that God answered our prayers, and did a miracle for us, even when we were doubting him and his Word, and we can think, that we can carry on in our life in the future, in the same way.
Jesus always responded to the faith of people, by doing a miracle for them, because he said that it was their faith that healed them, or did something else for them.