Originally Posted by
Guaran
Were you fighting withered aegis? Wraiths, Blights, and some others use Blighted Atrophy. This is +50% recycle (or something very close to that). Which means if you used Hero's Resolve while you had the debuff on you, the recycle would be 7 and a half minutes. So for 2.5 minutes, it stays fully greyed out. The timer will only count down once the remaining time drops below the abilities' normal recycle time.
If hunting in the Arena, Dragon ability Staggering Howl has a recycle modifier (-50%), and biped ability Dispirit is +50% delay, ice arrows have +10% recycle, Disconcert is +20% delay, Daunting Mist is +10% delay, and I am probably forgetting some.