I carry a Leatherman on my belt but my go-to knife is some crappy old 3-blader that belonged to one of the grandfathers somewhere. Part of the plastic has fallen off the sides but I wouldn’t replace it for love nor money.
Humans don’t have claws or fangs so a pocket knife is crucial when the need for sharpness arrives. I use mine a couple times a day to open boxes, trim a piece of string or to convince a plastic package to open properly. It’s my “metal thumbnail” and is always handy. Always.
One of my son’s has a knife my uncle gave him. It belonged to his grandfather who carried it during the Spanish American War. We had to put a Stag handle on it.
He also has a WWII era Nepalese Ghurka Kukri. Talk about razor sharp. I’ve cut myself looking at it on the shelf.