A clock is a very bad gift to give someone. This is connected to death and gives bad luck. In one way it is quite logic cause the clock is a symbol for the end of time that has come. So dont give a clock at all time.
Chinese Belief: As a present, do not give someone a clock. The phrase “giving a clock” （送钟） sounds similar to “sending someone off on his/her last journey” in Cantonese （送终）. Thus, it is very inauspicious and the older generations especially would frown and might even be angry if they receive one as a gift.