Apple Inc.’s top executive overseeing its Siri virtual assistant told staff that delays to key features have been ugly and embarrassing, and a decision to publicly promote the technology before it was ready made matters worse.

Robby Walker, who serves as a senior director at Apple, delivered the stark comments during an all-hands meeting for the Siri division, saying that the team was facing a bad period. Walker also said that it’s unclear when the enhancements will actually launch, according to people with knowledge of the matter, who asked not to be identified because the gathering was private.