Rhetorically, *why* was there a false alarm?

Residents of Hawaii were thrown into a panic Saturday morning after an emergency alert was sent warning of a ballistic missile threat. But officials minutes later tweeted that it was a false alarm.
"NO missile threat to Hawaii," the state's Emergency Management Agency tweeted at 8:20 local time (1:20 ET).
Rep. Tulsi Gabbard, D-Hawaii, tweeted: "This is a false alarm. There is no incoming missile to Hawaii."
https://www.nbcnews.com/news/us-news...icials-n837511