verb

fail to fulfil the hopes or expectations of.

I have no wish to disappoint everyone by postponing the visit

let down,fail,dash the hopes of,dishearten,dispirit,discourage,upset,dismay,depress,sadden,dampen the spirits of,disenchant,disillusion,shatter the illusions of,dissatisfy,disgruntle,chagrin,fall short (of expectations),bum out