Help needed with 30 second gesture drawings

For starters, here are some 30 second gesture drawings I’ve done using class mode: https://imgur.com/a/jvdGj3u

They are very bad. They don’t look in the shape of a human, and there’s no confidence in any lines. Nor do any lines properly imitate the models. I just feel unable to do that. I can’t figure out how to look at a reference and have my sketch match up in any sort of way. I’m told it doesn’t matter because I’m just training my brain to see the shapes, but I can’t imagine that’s going on when I’m not really learning these shapes since I can’t even imitate them. I cant get any lengths right or where I’m supposed to connect parts or how big something should be. 

I’m feeling like I should give up now since it might be a lost cause. These have worse anatomy than a preschoolers drawings.

My usual sketches take hours, an embarrassing amount of hours, because I don’t know what I’m doing. 

Any help at all is very much appreciated, advice at all on how to be able to draw these shapes or how I’m supposed to go about using these gesture classes. Anything works. Thank you.

I think you're harsh on yourself, because they do look very much like human bodies. 30 seconds isn't an amount of time that's going to let you fix a lot of (or any) mistakes, so when it's wonky it stays wonky. (maybe it's simply a timer that doesn't work for you, like are your 60 second sketches more comfortable for you?)

Personally I try not to put any value in what my 30 second sketches look like, because they're just warm ups. They're generally not great, but when I'm done with them it's a lot easier to work on something that's going to have more polish, as I've already made a ton of mistakes (like misjudging the size of the canvas etc, shoddy proportions, etc). Doing that doesn't prevent making more mistakes, but it makes them easier to spot and fix when I'm working on a more serious piece. 

Also: I don't think you should give up based on your work!
Hmmm... How to say this. Do you have a reason to stick to this, that is unrelated to how good or bad you are at it? I think it's good to pick up these type of studies when they serve a purpose, instead of just doing it because of the abstract goal of wanting to learn how to draw. It doesn't have to be anything deep or anything, just something that keeps you afloat when your sketches suck. (And I mean that in a "when the artist thinks their sketches suck" kinda way, because I feel like we all have days where we just don't like the thing we made.) 
If you have a goal that brings you joy, it's worth sitting through a ton of bad sketches for. For me at least.

ETA: What I mean to say with all that is: if gesture drawing is something that is not-fun for you in a way that it sucks all the joy/feeling of accomplishment/whatever-you-gain-from-creating right out of doing art, then it's def something you can consider giving up on. But it shouldn't be based on your skills, bc improvement is gradual and not always visible. (And even if you don't improve at all, that's fine too.)

However if you DO give up on it for this reason, please don't think you have failed. There's never one right way to do art, and figuring out what you like or don't like doing is succeeding at it actually.