Not only, a "good" knife can be measured by its sharpness (and still the 3x sounds very little scientific) but also by the durability of its sharpness, there is

Not only, a "good" knife can be measured by its sharpness (and still the 3x sounds very little scientific) but also by the durability of its sharpness, there is a a youtube channel[0] by a guy that makes blades out of "everything" and they are actually sharp, but how much do they last (and last sharp enough) is unsaid, and in the end of the citation it seems like they propose these HW knife as a replacement for plastic cutlery. [0] as an example only a knife made out of plastic bottle material (should be PE): https://www.youtube.com/watch?v=3ZnT31JeBTg https://www.youtube.com/watch?v=3ZnT31JeBTg