The watch likely symbolizes the archetypal idea of the passage of time. Quentin is constantly surrounded by "time" and he is always trying to understand how time in the past can influence time in the future. Quentin's breaking of the watch is his attempt to physically stop time from passing, this is foreshadowing for his own suicide. Because he fears time making him forget his feelings, he differs from Benjy who lives with no concept of time. Quentin was told by his father that time eases all sorrow, but for Quentin, to forget sorrow in the present is to think that his bereavement has no meaning and thus he has no meaning.
