Almost the very first thing I address as a Coach is about change. Change to improve. For change always comes with discomfort. In the beginning it is hard for the players to tell the difference between discomfort and hostility. The moment they feel discomfort they feel they are under attack. So I will normally say observe the intention, the motive. If the intention is to help you improve and the motive is to build then it is mere discomfort. If the intention is to stop your progress and the motive is to destroy then it is hostility. But in the beginning it feels the same and sometimes sound the same. For change starts with asking the hard questions.
But with careful observation we can learn to tell the difference.
In fact sometimes sweet words are meant to destroy. Do you have any experience of that?