now these braided ones in all the pics here are what i consider to be fobs,not lanyards.its not a fact or anything,just my way of looking at it.
i put fobs on my smaller knives like the ratshaker or busse HACK and it makes it easier to get them out of the sheath.with those tiny little handles its sometimes hard to grab them,especially if you needed to do so quickly.the same would go for trying to dig a smaller pocket knife out of your pocket like the SAK in horndogs pic.their great for that.
for my uses a lanyard is a loop at the end that you can actually put your hand through.i used to have them on all of my knives but came to the conclusion that i didnt really use them 90% of the time and they got in the way more than anything.
instances where i do use a lanyard is when i'm up in a tree stand bow hunting,have to use my knife and dont want to risk dropping it from the tree.with my hand through the lanyard it is in a way tethered to my hand.the same would be true if i was using a knife over a body of water.
i also would use one if i where stabbing the knife into something.maybe a log for whatever reason.with your hand through the lanyard it makes it almost impossible for your hand to slip off the handle,over the guard and down onto the blade,slicing the insides of your fingers,probably to the bone.it takes a little adjusting to get it just right but is well worth the effort.
a lanyard might also come in handy for knife fighting.any weapon you pull out can be taken and used against you.a lanyard could prevent that.also,if you where knocked to the ground or unconscious the knife would have a better chance of staying with you as opposed to flying out of your hand leaving you separated from it.
i think the braided ones {fobs to me} look good on knives but dont serve much of a purpose some of the time and with their bright colors they also tend to bring much attention to the knife where it otherwise might've gone unnoticed.in new york you want your knife to go unnoticed unfortunately do to political correctness,especially if its an expensive one.dont need the cops taking my strider.
braiding your own isnt as hard as it looks.you'll have it down in 10 minutes and can really monkey around with different colors.