The worst feeling is writing so many lines of code knowing you could do it in a more concise way if you just had time to think about it but you don't.

Java:
Primitive streams. Their need to exist is a monument to legacy failure.

VB.net
OrElse and AndAlso short-circuiting operators. The language designers were too fucking lazy to process logic, so they give specific keywords for those cases.

PHP
Random Hebrew error messages

JS
Eval. It can be used responsibly, but most of the times you see it it's because someone fucked up.

C#
Lack of Tuple destructuring in argument specification. Tuples were added, and pattern matching was added, and it's been getting better. The gear grinding starts with how Tuple identity assignment in arguments is handled. Rather than destructuring into the current scope, it coalesces the identity specification into a dot property of whatever the argument name is. This seems like an afterthought given they have ootb support for ignore characters.

Typescript
This will probably be remedied in the next version or two, but Tuple identity forwarding between anonymous scopes normalizes to arrays of union types, because tuples compile to typeless arrays. It's irritating because you end up having to restate the type metadata in functional series even when there is no possibility for any other code branch to have occurred.

1) Learning little to nothing useful in formal post-secondary and wasting tons of time and money just to have pain and suffering.

"Let's talk about hardware disc sectors divisions in the database course, rather than most of you might find useful for industry."

"Lemme grade based on regurgitating my exact definitions of things, later I'll talk about historical failed network protocols, that have little to no relevance/importance because they fucking lost and we don't use them. Practical networking information? Nah."

"Back in the day we used to put a cup of water on top of our desktops, and if it started to shake a lot that's how you'd know your operating system was working real hard and 'thrashing' "

"Is like differentiation but is like cat looking at crystal ball"

"Not all husbands beat their wives, but statistically...." (this one was confusing and awkward to the point that the memory is mostly dropped)

Streams & lambdas in java, were a few slides in a powerpoint & not really tested. Turns out industry loves 'em.

2) Landed my first student job and get shoved on an old legacy project nobody wants to touch. Am isolated and not being taught or helped much, do poorly. Boss gets pissed at me and is unpleasant to work with and get help from. Gets to the point where I start to wonder if he starts to try and create a show of how much of a nuisance I am. He meddle with some logo I'm fixing, getting fussy about individual pixels and shades, and makes a big deal of knowing how to use GIMP and how he's sitting with me micromanaging. Monthly one on one's were uncomfortable and had him metaphorically jerking off about his lifestory career wise.

But I think I learned in code monkey industry, you gotta be capable of learning and making things happen with effectively no help at all. It's hard as fuck though.

3) Everytime I meet an asshole who knows more and accomplish than I do (that's a lot of people) with higher TC than me (also a lot of people). I despair as I realize I might sound like that without realizing it.

4) Everytime I encounter one of my glaring gaps in my knowledge and I'm ashamed of the fact I have plenty of them. Cargo cult programming.

5) I can't do leetcode hards. Sometimes I suck at white board questions I haven't seen anything like before and anything similar to them before.

6) I also suck at some of the trivia questions in interviews. (Gosh I think I'd look that up in a search engine)

7) Mentorship is nigh non-existent. Gosh I'd love to be taught stuff so I'd know how to make technical design/architecture decisions and knowing tradeoffs between tech stack. So I can go beyond being a codemonkey.

8) Gave up and took an ok job outside of America rather than continuing to grind then try to interview into a high tier American company. Doubtful I'd ever manage to break in now, and TC would be sweet but am unsure if the rest would work out.

9) Assholes and trolls on stackoverflow, it's quite hard to ask questions sometimes it feels and now get closed, marked as dupe, or downvoted without explanation.