Skill recharge time (as noted by the icon in the game) is the amount of time until a skill can be activated. Successfully activating a skill or having a skill interrupted during activation will cause it to begin recharging for its listed recharge time (a skill with no recharge listed will be available immediately). When a skill begins recharging, the skill's icon on the Skill Bar is darkened, and brightens in a clockwise motion, giving an indication of when that skill can be activated again. Adrenal skills cannot gain adrenaline while recharging and will lose any accumulated adrenaline if they begin to recharge.
After a skill has been successfully activated or interrupted, it begins recharging for the specified amount of time (or until a Morale Boost). Some skills, as stated in their descriptions, will disable themselves after activation. Some skills will cause skills to become disabled for "an additional" amount of time. In that case, the specified time is added to the normal recharge time of the affected skill.
When a skill's activation is stopped by intentionally cancelling it or by skill failure, the skill will not begin recharging and will be available immediately. Any energy or adrenaline cost paid to begin activation is not refunded, and any exhaustion incurred will not be removed.
Receiving a Morale Boost will recharge all of a player's skills. This is the only way to recharge Resurrection Signet, Sunspear Rebirth Signet, and the celestial skills. Morale boosts will not charge adrenal skills.
Recharge time will not stack to exceed -50%. Recharge times cannot be reduced below 1 second. Such effects will also not affect the recharge time when a skill is disabled. When an effect such as Mantra of Recovery and Ritual Lord says they cause something to "recharge faster" by a certain percentage, they actually mean recharge time will be reduced by that percentage. Recharge time stacks multiplicatively, meaning Glyph of Swiftness (25%) and an Essence of Celerity (20%) will reduce your recharges by 40% rather than 45%.