It's also interesting to see the reaction to the price - to some, your price points are absurd, but I've met a few coffee enthusiasts who have spent 4x what you're pricing for a grinder.
Best of luck!!
They are giving actionable advice on how to convert more sales. That's the whole point of Show HN, and helpful to the author.
When a bunch of people with experience in a domain tell you that you can vastly improve something in that domain, it's generally a good idea to listen and consider their critique instead of calling them "keyboard ticklers".
No curiosity or questions or clarification about how it makes better coffee, spare parts availability, food safety, where and how it's assembled, thoughts about the aesthetics of the unit. Lots of "the site sucks, I bounced."
Edit: happily, there's more and better critique on the thread now than when I posted the GP comment.
Their critiques might be fair, after all the website is by far the furthest part of this from my area of expertise. But hopefully, people will prefer a good espresso machine with a bad website to a bad espresso machine with a good website!