Bottom line...you need to carry a knife that will do the job you need it to do, and do it consistently and well.
If you only need to cut string, the jagged lid off an old tin can will do. Heck! A pair of cheap fingernail clippers will probably do.
If you use a knife everyday and it's a tool you depend on, you might want to go with something a little better. If you want to pay for the added bling of fancy scales or handle, that's your choice. If you want good quality steel that holds an edge, that's your choice, too.
If a three-dollar, gas station. Pakistani knife fits your needs, who am I to argue with you? That's the great thing about knives. There is such an endless variety out there that just about everybody's needs will be met.
This one seems to find its way into the front pocket of my Wranglers a good percentage of the time. It belonged to a forum member's wife's grandfather. It was made around 1919 or 1920. It was given to me with the instructions, "This is a working man's knife. Use it!" Believe me, I do. It does everything from cutting hay bales to opening feed sacks to cutting whang leather to repair a piece of tack...all pretty much on a daily basis. It's a great knife made with great steel.
If I'm not using that one, this old work worn Case trapper will be in my pocket. Either knife will serve the purposes for which they were intended.