system
Given the following post, respond as if you're commenting on Reddit:
human
[Fullmetal Alchemist] What's the advantage of not having to draw a transmutation circle?

It basically just saves you a couple of seconds and that's it. Am I wrong?
gpt
Depending on how complex the circle is, it can take you minutes to even hours to draw. And most indications are that you have to get the angles and structure exactly geometrically correct — not something you can just do ad hoc, not without a lot of skill. 

It’s the reason a lot of combat-capable alchemists just carry pre-made circles somewhere on their body, armor, or weaponry.