(rambling about
#languageLearning, might be nonsense beware)
I think there's a trade off everyone needs to make when they learn a language, that they don't realise they need to make.
They have to decide how much they value pronunciation - generally at the outset.
The reason is because, if we develop an accent, it would take a lot more work to correct it than if we learn to pronounce properly from the outset. Having a lot of deeply ingrained "bad" habits, is harder to work with than a blank slate.
I see two paths, a person that from the outset is at complete peace with the prospect of sounding like a foreigner, and they do a lot more output from the start and don't learn about pronunciation or try too hard to get specific feedback on pronunciation. This person will get comfortable and fluent much quicker, I would imagine but they'll sound distinctly like a foreigner (which they may have literally no problem with).
In their minds, they won't realise it, but they'll very likely be converting the language they've learned into the phonemes of their mother tongue very quickly. Getting better, in some sense will be, converting the sounds from the language you're learning to the sounds of your mother tongue quickly.
Another path is where you delay output until you can hear very well, and have an explicit focus on pronunciation. You use a lot of time and energy that could go into just speaking and using the language to really familiarise yourself with how it sounds. You get feedback on how you are pronouncing things with a teacher and really try to get it right. Learners of a language make lots and lots of mistakes, if you insist with a teacher that they prioritise pronunciation, then you will 100% miss out on other feedback. We make too many mistakes to get corrections on everything, so teachers have to pick and choose what feels the most off to them, what's the most salient.
I'd imagine focusing on pronunciation and getting intimately familiar with how a language sounds from the outset would add a lot more work, but when its done it'll be easier to parse the language, especially mumbles, slurred or fast speech. Even though I'm using the word "pronunciation" hear, I mean something like getting very familiar with how a language sounds, and pronunciation will affect perception. It's very likely that pronunciation mistakes people make, map on to perceptual blindspots - that they aren't hearing the language effectively. However, you can't get proper feedback on how you are perceiving a language directly, because a teacher can't see into your mind. Working on your pronunciation is the only way.
Neither choice is *better* I think, it's just that it's a decision people make and commit to without realising that's what they are doing. Practice doesn't make perfect, practice makes permanent. It's not repetition itself, but repetition with feedback loops that leads to improvement. If you repeat the wrong pronunciation over and over again, without any feedback, you'll only engrain the habit of pronouncing things this way. It might make sense to decide you are okay with this, but most people don't knowingly decide this.