Old School D&D had a multitude of ways to kill you, but none more scary than shit that turned your ass to stone. And there were all sorts of these things...medusae, basilisks, gorgons, cockatrices. As a DM, I love inlapidaters; as a player I despise them. One of the major issues when running one of these monsters is how to fairly apply their special abilities. Gorgons and cockatrices seem to be easier, as the players can either run away or avoid physical contact. Medusae and basilisks, however, have gaze attacks. It was never very clear how these operated. I mean, everyone who plays D&D has probably read some Greek mythology and seen Clash of the Titans: you use a mirror when you're fighting a medusa. But what if you're one of the unfortunate rubes who is just wandering through a dungeon when the encounter takes place?
Viewing these monsters through the lens of "modern gaming", we should have all sorts of rolls and precautions, fifty chances of avoiding the gaze, whatever. Old School, however, isn't as forgiving. It tries to emulate epic fantasy, which means some people unfortunately are turned to stone. Sorry. And that's how it should be. We already have a mechanism for avoiding the gaze of a medusa, it's called Save vs. Petrify/Stone. You stumble into a room and a medusa looks at you, well, roll the dice to see if you survive. Perseus was warned ahead of time. The PCs may not be so lucky. But the DM shouldn't just have a random medusa in a 10x10 room with no indication that anything is out of the ordinary. Perhaps. A sloppy medusa might have left stoned adventurers (both kinds) in a few places around her lair. Smart players would realize the possibility of an encounter and take proper measures. A smart medusa would try to entrap the characters, her trophy room away from prying eyes. In the latter case, someone is probably going to die. It's not fair in the modern sense, but again, don't go into dungeons unless you're seeking trouble.
I suppose this is mostly a gripe with "modern gaming", because we used to avoid those types of monsters in all the AD&D games I've ever played in until we got powerful enough that they weren't a real threat. Once you have a 12th level Magic-User, getting turned to stone is extremely inconvenient but not insta-death. Unless the MU gets turned to stone; you're screwed. Then again, a 12th level MU in a party of characters of comparable level probably won't be killing medusa as they don't have enough treasure to justify the risk. So, it's the low level PCs who try to kill medusa. Or at least just steal their stuff. The trade off between risk and reward is weighed, and if you're 4th level, it's a good payoff. Yes, you should avoid those things, but PCs are heroic adventurers, which means they sometimes do things that have a high chance of death. If the DM reduces the risk, the encounter is made meaningless.
It sucks to have a character die, that's for sure. But it also sucks to lose a football game or get beat in chess. After a lot of introspection, I've decided I actually despise roleplaying in its modern form. There seems to be a major shift from playing a game to doing some sort of improvisational theater. That's fine. But, hey, Shakespeare killed off a lot of his lead players; why are DMs so loathe to do so in rpgs? How can there be any meaningful storytelling without loss? I like playing games, some people want to explore the psyche of a fictional character. More power to them. But, again, how does making death an impossibility create a better experience? Modern rpgs seem to use game mechanics as a crutch to prop up stupid decisions by players. No game mechanic can ever replace good judgment. These same mechanics generate a sense of entitlement to boot. I'm probably never going to play a rules-heavy rpg ever again because of this. Oh sure, I like buying and reading them, but playing...I want epic, heroic fantasy, not an exercise in character building. Heroism cannot exist without extreme risk, a very real possibility of loss. If you're going to nerf monsters like medusae and cockatrices, you might as well just make your characters 1000th level and say you won. No one wants their PC turned to stone, but if it happens, 3D6 down the line.