Except there is and there is way more to it. The biggest thing is not clipping your auto attack, which is extremely easy to do.
What’s the speed of your weapon? Is it better to clip your auto shots as a result?
The next thing is understanding how long it takes your group to kill a boss, and understanding your current level of gear. Every boss is different and the time will shorten as your group improves, so this is an ongoing process.
Can you get away with adding arcane and multi shot every single time it’s off cool down without having to switch to viper? If you can, can you still maintain a perfect rotation and not clip your autos? If you can only do one, which one is better for the situation and mana consumption compared to DPS?
Do you have enough time to pop bestial wrath and rapid fire more than once on the fight?
If you can pop it more than once, are both of those times ideal, or is it better to use the cooldown at one point in the fight instead?
When should you use your haste potions? Are you watching the other buffs you get that proc and add to haste so you aren’t stacking the wrong buffs?
The list goes on, but there’s a reason people have similar gear, similar fight duration, not cheesing the fights, and a 800 dps difference in eDPS for the fight.
3 buttons turns into a lot to think about and manage if you want to perform on a top-tier level. Not many people are capable of coming close to hitting their max DPS because of how many factors that actually goes into it beyond just the rotation itself.