It is no accident and it is not mere convention that with thinking we say “I changed my mind” and with action we say “I changed my ways” but with morality we say “I had a change of heart.” Some things we do; other things are done to us. But what is done to us — what or who does this doing? Your response to this question indicates what might change if you were to have a change of heart.
Spot on! Sadly, too many people bypass the thinking and go straight to changing heart, mind and behavior.
Events — esp traumatics ones — can effect a change of heart, but I agree that all too often people neglect thought’s potential to actively spur these changes and instead passively wait for change to happen to them, or they dig in and resist change altogether.