Let me tell you a story of a Svedish Evil Overlord's roleplaying experiences.
I've had a rather decent interest in tabletop games since my early teens, since I found my parents' copy of 3rd Edition DnD Players Handbook. I had no previous idea my parents were into DnD. Turns out they used to play regularly a good 15-20 years ago, during the good old AD&D days. Obviously they haven't played much since then since life and family happened, but eh. So I sat down and read these books, and, obviously, wanted to start playing. So I roped in my brother and a few friends and acted as a DM for a campaign. Obviously, I was a pretty horrible DM at that time, but no one really noticed that, and we had much fun doing various DnD shenanigans. Actual roleplay in these sessions were rare though.
Fast forward to about five years or so ago (Five years? Nine Hells. I feel a bit old now!) where I first got my first online tabletop RPG experience, and my first proper roleplaying experience at that. I don't quite remember how, but I managed to stumble upon a small homebrew system designed primarily around Final Fantasy (As I was a big fan of the series at the time), as well as the community around it. Turns out they had a few IRC channels through which they played, so I joined up and found a group to play with. My first character? A Moogle Black Mage who was perpetually angry. Yeah. He was fun to play as, but not really a shining ideal of character design, and aside from a few moments of ingenuity, served mostly as the group's comic relief.
In a separate campaign (still using that Final Fantasy system), this time playing with only a handful of what was originally a group of about 20-30 people, I created my first
good character (and simultaneously also one of the most embarassing): Relan Crescent, son of a retired adventurer and previously an apprentice mechanic, now a prodigous young mage after discovering a magical (albeit slightly cursed) amulet and receiving a few years of training at the hands of one of his father's former companions. Full of adventurous spirit and eagerly wanting to follow his father's footsteps yadda yadda you know the drill, I had every intention of playing a self-confident and brave, albeit rather naive young lad. Imagine my surprise when he, at the end of the campaign, is a broken, emotional wreck one step short of succumbing to homicidal insanity.
The campaign started with all of the PCs in a cell. Most people had winded up there for minor crimes (some guilty, some innocent). Relan had accidentally
obliterated a building, after his amulet spontaneously decided to emit a fuckhuge burst of eldritch energy. Before they can all be properly processed, some guy who I can't remember drags all of us along with an NPC scholar in order to raid some ruin for an artifact. We retrieve the artifact, narrowly escaping death in the process, and suddenly the guy who roped us into this suddenly wants to kill us all because we know too much, and sends a fuckton of guards on us. Somehow we get away (I think the scholar put everyone to sleep... somehow) and retreat to a nearby insignificant village. So, this mage basically strolls through a city on what otherwise amounts to be a completely normal day, when suddenly the amulet he bears outright destroys a building and everyone inside it, he gets drafted against his will to explore an ancient ruin that almost killed everyone, and at the end of the day is now a wanted criminal, hiding from the authorities. Entirely through no fault of his own.
Things just go downhill from there. The amulet he's wearing? Turns out that amulet was created long ago by one of the most powerful and malevolent mages known to man. Even worse, the amulet is going all kinds of haywire because
he is directly related to this mage. The amulet is in itself infused with the power of what in this setting amounts to be a god, the god in question being a
god of destruction, and the amulet can reportedly be used to
summon it. All in the hands of a young mage who has no idea how to control it. The party eventually encounters the main villain, who, among other things, is also related to this mage and wants to kill Relan so he can take the amulet from him (as no other method of removing this amulet has been discovered so far). For whatever reason, he exits stage left without killing him (or we simply managed to escape and my memory is just being shit). All while the amulet is slowly eating away at his sanity.
The campaign continues. The party joins up with an airship captain (did I mention this was Final Fantasy?) and starts to thwart the villain's plans because whatever he's doing can't be any fucking good. With every session, the universe decides to collectively shit on this young mage by throwing all manners of hardships on him. He discovers yet more immensely dangerous powers he now realizes he wants nothing to do with. A few of the other party members, the only people he can really relate to at this point, starts dying. He finds love, but that love is unrequited. Stress, fatigue, and an ancient evil amulet is by every passing day making Relan more and more unstable (which eventually causes him to start misusing his already dangerous powers), and when he starts to complain about this, no one gives a shit and and people just tell him to shut the fuck up.
So, at the end of the campaign, what started out as an adventurous and eager young man is now socially reclusive, incredibly jumpy, and pretty much an emotional wild-card, equally as likely to fly into an unimaginable rage as he is to break down and start crying. Day by day he comes to the realization that he has no real control over his life, no one cares for him and all he's ever good for is destroying things. Then... the campaign abruptly ends because of drama between a vital player (not me) and the (very much a troll) GM. Whatever happened to Relan? No one knows. (It's actually fully possible that the DM in question finished up the last events of the campaign after I left the group, but that's not here nor there).
So what has this taught me about roleplaying?
While this may vary from person to person, roleplaying with some sort of system or other kind of moderation makes it much easier to make a believable character, because you can't just make them arbitrary good at everything and make them succeed at every single task. You can't say "I bury my axe in this guy's skull, killing him", you have to say "I try to bury my axe in this guy's skull, in an attempt to kill him" and then roll to see if you succeed. Good roleplayers won't have a problem with this, but inexperienced ones would do very well to have some sort of limiter in place.
A DM (or equavilent) that helps maintain a cohesive narrative and story does fucking wonders for roleplaying.
Character development more often than not tends to come naturally. While you can certainly make estimations, I've found my characters develop in a way that was completely unexpected, several times. Just look at Relan! I had no clue I'd wind up in that position at the start of the campaign.
Even if you try to avoid cliché, it's pretty easy to stumble upon it accidentally. This isn't inherently a bad thing.
Obviously, I've come a long way since then, and have continued with roleplay in several settings (whether Final Fantasy-type settings as seen above, more traditional fantasy like DnD or Pathfinder, and more recently sci-fi settings such as Space Station 13, or a mix of the two like Shadowrun) and you can occasionally see me writing up characters for the hell of it. Some of the characters I've played since then include:
An elven sellsword who is very down-to-earth for an elf, as well as very analyctically minded for a warrior, and completely oblivious to the women that's hitting on him. (Pathfinder)
A young child at about 15 years old, possessed by an ancient magic tome, who wants to unlock the secret of time travel. (FF-system mentioned above.)
The Chief of Engineering on a space station, being the sole pacifist and general reasonable person on a station where everyone and everything is homicidally batshit insane. (Space Station 13)
A robotics scientist on the same space station who is foulmouthed, aggressive, and all in all pretty much a horrible person, who would beat your face in with a crowbar if you so much as looked at her the wrong way. (Space Station 13, although she's about to be repurposed and slightly redesigned as an an NPC in a certain Shadowrun campaign...)
A smooth-talking operative with an emphasis on persuasion and con-artistry, as well as being a prominent womanizer. (Shadowrun. Unlike what Smash would gladly tell you, the womanizing part is NOT the defining part of the character.)
Wow, that turned out to be a pretty fucking huge wall of text. I guess I'll just continue playing 4X games for now.