Kithabel is sitting on the flat top of the tallest tower of her palace, forcing the rain to decline to fall on her, taking a break insofar as she ever takes a break. She has no constructive ends to pursue right now, so she's playing with the lightning in the clouds overhead. She doesn't want to try taking a direct lightning strike yet - she could probably take it, but only probably - but she can tell it to arc here and there in patterns, she can ball it up and watch it roll through the air, she can make it turn colors. She's making sure none of it hits the town, and if it starts a fire in the woods she'll take care of it, but at the moment it's a toy.
"Most people do little stuff, at least by accident, but sorcerers are uncommon. There's nine territories if you count mine in this country. Why don't more people pick up your kind, if it doesn't require constant work to maintain momentum?"
"It requires work to learn how to use it. You don't get worse at things, usually, but it's still a skill to acquire. Doing things by accident is unheard-of; it took me ages to learn to light a candle."
"Can you teach me?"
"Maybe? But it's hard, at the beginning anyway, and if splitting your concentration isn't good for momentum then it might not be worth it for you."
"I have some spare time. I do need to spend a lot of time doing magic every day, but I'm pretty on top of that. And some of my day can be spent floating, I don't have to concentrate to do that anymore, which isn't good variety but it's not nothing like sleep, either."
"It's pretty simple; you stare at it for hours meditating about how you're a magician who can rewrite the rules of the universe with your mind and it's an inanimate object and it has to obey you. After that doesn't work, you do it again. When I eventually got it, it was after hours of not even noticing time had passed, with months of failures beforehand."
"I'm pretty sure if I do that I'll just wind up -" She conjures a candle; the rain doesn't hit it, either. It catches fire. "Do sorcery the usual way."
Maybe it is the same magic, and people here just have a very strange way of collecting power."
"I don't think so. Yours seems to be a skill. If I don't do any magic for, oh, two days, I'll wake up and I won't be any better at it than some random person who only rescues burned food and cleans their gutters with magic and nothing else. Not even specialist-grade."
"I was thinking of that as part of your world's strange magical capacity issues, but if it isn't a skill then it can't be the same. Where I'm from, only a magician can clean a gutter with magic. Though they usually have better things to do, of course."
"Here it's momentum. You gather momentum and you can do more and bigger things; you can channel that into a specialty, like healing or architecture, or you can go for sorcery. The official cutoff point around here for whether you're a sorcerer or not is flight, although if you don't do anything but fly you lose your general momentum and turn into a flight specialist. So you could fool someone into thinking you're a sorcerer but then they'll think you can do anything you want."
"I am a magician. I am professionally able to do whatever I want; people thinking it's a bit more literal than usual isn't a problem."
"What do you mean, professionally able to do whatever you want?"
"Unsolvable problems, impossible tasks, that sort of thing. Nobody expects magicians to be truly infinitely powerful, but it's bad for business to be unable to do things. So my team and I...do them."
"Please remember I'm coming from a background of sorcerers being it in the magic department, and given enough momentum we can effectively do whatever we want."
"Ah. Magicians can do effectively anything, but few individual ones can do everything. The things people hire magicians for aren't necessarily directly using magic; it's more problems like turning an army around, or dethroning an aristocracy of vampire cows, or convincing two politicians to hold a halfway fair election. As I said, impossible."
"...Why go to magicians for problems having nothing to do with magic?" (Kithabel causes a dramatic thunderclap overhead for effect.)
"The phenomenal cosmic power comes in useful, but mostly it's because a magician is a professional problem-solver. And non-magical people, most of the time, have non-magical problems. Do your people only ask for help when it's a magic-related problem?"
"They wouldn't want to waste a sorceress's time with something that didn't involve magic. I'd lose momentum. I need to be on the ball if I want to be able to resurrect the dead before I'm sixty."
How many sorceresses above sixty are there?"
"I don't know exactly how old everyone is, but decent momentum lets us live indefinitely."
"That's definitely not normal, or there'd be a lot more magicians everywhere else. Why is anyone here not a sorcerer?"
"Because sorcerers can't do a whole lot besides be a sorcerer. Slip up and you have to start over."
If that applied to magic, I for one would have stayed a thief."
"...Interesting career switch."