Suspension Of Disbelief on character mistakes

There exists a very fine line between "yeah, this guy fucked up a bit" and "come on, there is no way this guy is this stupid", but here's a question - where does it exist for you?

It depends on the character. There's no one firm line that applies to all characters.

Usually it depends on if I could see myself making the same mistake. Basically, if I can figure out a better solution, within less time, and with the same information they have, then there is a problem, especially since I'm not that smart.

Ok, that response of mine was kind of snippy. I apologize for that.

As Mr AHR said, it's going to depend on how the character has been presented up to that point. If so far he's been preternaturally capable and always makes the correct choice or knows exactly what to do no matter how bizarre the situation, then any mistake will be jarring to the reader — they'll think, "He's done <all these other things> perfectly, and he can't do <this thing>? I call bullshit." But if you have drawn him so far as having limits, them mistakes or failures that fit with those limitations or are functionally equivalent to them will probably pass muster.

But the thing is, in real life, people commit mistakes, no matter how capable they are. Even within the field of their own capability. Nobody does anything 100% perfectly all the time, sometimes a screw-up is just a screw-up. I know that myself from doing very obvious and pathetic mistakes in things I'm supposed to be good at, sometimes right after being good at them. Sometimes it's a habit hitting wrongly, somtimes it's nerves, sometimes it's lack of sleep or tiredness, and sometimes it just happens.

But when a fictional character has that screw-up, the audience most of the time calls bullshit. Like the very premise of a chracter being flawed is called unrealistic now. Either the character gets an "idiot" brand or the audience rushes to defend the character and present them as an infallable super bat-entity with a mega-perfect mind. I guess what I'm asking is about writing a capable character who is still capable of mistakes?

I haven't really noticed that happening as a general rule, only in particular parts of Fan Dumb.

The key to allowing a character to make a mistake and not have it come across as the hand of the author at work is simply to foreshadow it. Reveal that while they are generally quite competent, they have occasionally made this particular mistake before. Or set the scene in such a way that making this mistake is in keeping with their established character, and how they feel about and understand the situation.

This might be helpful.