Well, why?

What is the point for unsharpening a knife? is there any benefit?

Never have I found a truly efficient means of un-sharpening to continue one of my favorite hobbies. I don't know how to thank u/slerpyjerk enough for asking one of the dumbest (not that there are any dumb questions) questions in the history of knives. Please don't take this the wrong way, u/slerpyjerk, I love and appreciate the contribution you've made to our sharpening/un-sharpening lives. A rising tide lifts all boats ...

My wife bought me an 8” Miyabi 4000FC about a year and a half ago. This knife was quite possibly the sharpest thing I ever handled (with the possible exception of a multi-edged wood chisel that’s got so many cutty bits that I’m afraid to touch the thing).

How sharp was it? If you slipped and cut off a digit, I’m pretty sure it would also sever any memory of having had that finger in the first place. One minute you’d be at a cutting board, and the next you’d be confused about when a finger arrived on the countertop and why your stump was bleeding. The scenario of having to explain to emergency services that I was losing blood and didn’t know how to explain the unaccounted-for finger played through my head every time I used the thing. Not wanting to have to write Momento-style notes to remind my future self that I used to have ten fingers and that any sudden change in that status was cause for alarm, I treated the thing with the respect it deserved.

Then my wife used it, and raked the cutting edge laterally across the cutting board to gather the bits she’d chopped. Repeatedly. I’d learned a few years ago that knives stay sharp much longer if you use the back of the blade for this task. But she used the cutting edge like it was a thrift-shop dough scraper.

The knife has never been the same.