set (oneself) up for a letdown

set (oneself) up for a letdown

To set one's expectations so high that one will inevitably be disappointed by the outcome. Sometimes hyphenated as "let-down." I know you're really excited for this movie to come out, but I think you're setting yourself up for a letdown. John was so convinced that his relationship with Mary was perfect that he set himself up for a let-down in the long run.
See also: letdown, set, up
Farlex Dictionary of Idioms.
See also:
  • in demand
  • get a makeover
  • have a makeover
  • give (one) a makeover
  • bleeding edge
  • bowler hat (one) out (of something or some place)
  • cop on
  • hit and miss
  • hit or miss
  • hit-and-miss