"If ye then, being evil, know how to give good gifts unto your children: how much more shall your heavenly Father give the Holy Spirit to them that ask him?" -Luke 11:13, KJV.

Most parents want what is best for their children, and do their best to give their children the things they desire. God looks down on us as a Heavenly Father, and He too wants what is best for us. He looks for what He can give us that would be beneficial to us. If He decides not to give us something, it is probably because it is not what we need. (A hand grenade may look like a fun toy to a child, but not parent in his right mind would give that to his kid. Even so, God will not give us something that will destroy us.)