Version 1 - you can have all the quality control and still have issues because..... limits of human mind. You cannot test for all real world scenarios because customers have unique situations the designer never thought of. You also have a new production line which needs to debug, newly trained staff to test a new product.
There is also the limit of the buyer's mind. For example, when I saw the Anker (not Zolo) Soundbuds Life, I thought it a clunky looking big product but I got gifted one for free and I found I liked it and use it most of any other prior audio product. I also got some Soundbuds Life+ and I love them so much my Bose QC35 don't get used. I would not have predicted that.
Conclusion: designer and consumer both learning.
This product Liberty+ is version 2, the Liberty being version 1.
Version 3 is a good method - the designer has had multiple feedback, been surprised about customer feedback and adapted.
The Liberty+ I got gifted by Anker and I gifted to another and they really like them and I look at them and see room for improvement, making them smaller and/or better battery life.
My own personal prediction for these fully wireless buds is they shrink further and the feature of broadcasting inside the outside noise will be likely the "killer feature" where you keep the buds in your ears 24x7 and use them to augment reality. They will have AI and learn and will eventually act to protect you, they will alert you to threats via sensing sounds like approaching vehicles. Noisy rooms, noisy pubs, etc, all become enhanced vi filtering to what matters to you.
Hearing is handled in the human brain different to vision, it is a "lightweight" task and it is processed faster, so audio can be superior way to get response than vision.
The current habit of a pedestrian who has wired buds in and walks into a car or into a cyclist will then be gone.
The current habit of shouting in a noisy place, will be gone.
Hearing damage due to too-loud music to drown out ambient noise, will be gone.
We just need the tech to evolve.