Meaning: Telling someone they are doing a good job helps them want to do even better, but telling someone they are doing a bad job makes them not want to try.
Choice of Words: Encouragement involves providing support and motivation, motivates implies inspiring or stimulating someone to take action, criticism suggests expressing disapproval or negative judgment, and demotivates means reducing someone's motivation or enthusiasm. The sentence emphasizes the positive impact of encouragement in inspiring action and the negative consequences of criticism in discouraging it.