Cooldowns Reduce Depth

In practice, my biggest complaint against cooldown-oriented design is that it tends to take a way a lot of the tactical depth in a situation. As a brute-force stopgap to "solve" poor game balance and make up for problems in other mechanics, many such games feature abilities that are extremely powerful unless mediated, and often in very large quantities. This usually raises the question: "if my abilities are all so powerful, why am I not just using them all the time?"

A game like Dragon Age II, for example, can see the player activating upwards of ten different abilities throughout the course of a single battle, and even the same ones multiple times over if the fight goes on long enough. Actually using them thoughtfully isn't just completely unnecessary, it can actually be a liability. As most of the abilities in Dragon Age II are instant-use and either have some sort of stun or damaging effect, they quickly become near-indistinguishable from each other; what's more, the tougher enemies can be heavily resistant or immune to the effects of these abilities, meaning that using them in a way that the situation might call for them simply isn't very effective.

Dragon Age II does have mana and stamina as additional limiting resources, but they are far less important than the cooldowns themselves. Quaffing potions is usually more than enough to get through, and potions are both plentiful and fairly cheap, so most players will never run out of them. Of course, even the potions have cooldowns on them, to prevent them from being used over and over. Once again, the question comes up: "if potions are so powerful as to require cooldowns, why aren't they made more expensive, or why can't there be another game mechanic governing their use?"

The Witcher's toxicity mechanic prevented the player from drinking potion after potion, for instance; not only did it work well to balance them, it also fit the game's lore like a glove. Dragon Age II has none of this tact or finesse - rather than turning weaknesses into strengths through smart game mechanics, it slaps more timers on the player until the exploits disappear.

Cooldowns also reduce the value of long-term planning. As discussed above, many games are built around the question of using abilities at the right times, and as contingencies for failures. While cooldowns can retain some of the value in planning (for instance, some high-level MMO play relies on calculating perfect ratios of damage input/output/healing), these dynamics are not intrinsic to cooldowns - you can do the exact same thing with a mana bar, or with limited uses of abilities, or providing harsher risks for misusing abilities.

The end result of all this hard limiting is a system that isn't just rigid and limiting, reducing the sense of control and interactivity the player has, it also ends up largely reducing combat from making smart and tactically valuable choices to a series of quick time events: press the hotkeys as they light up to win. At absolute worst, this can create a feeling of "false interactivity", where the player isn't so much making smart decisions within the rules as he/she is playing a pattern-matching game. Instead of "what abilities should I use, and when?" the questions posed to the player are "press all your buttons as soon as you can." The resemblance to quick time events, and their pattern-matching mechanics quickly becomes apparent.​