Depends on what I'm marking. I do a lot of shallow water fishing around rocks and reefs, but most are not marked on charts (either electronic or paper). At most you get a wash rock here and there within the shaded blue area along the shoreline. Gotta find em and mark em. I don't even label those. I also mark the edges between two bottom types when that matters. Those don't need labels. Hot spots get a number, and I reference the number in my logs.
I generally label them with the type of fish caught if I feel its going to be worth a return trip. If not I just use the number as a marker just so its a reminder to maybe stop in there and try if Im feeling up to it.
A couple of years back my long-time fishing companion and the best king fisherman I've known passed on to the great beyond. His grandson inherited lots, including the boat. He just started a charter business, and confided in me that granddad left behind a very-well marked GPS.
Grandson is a good fisherman in the first place, and with that doctored up GPS, I'd say he has a very bright future on charter.
Makes me reconsider some of my marking practices. No grandson in my wake, but a son-in-law who loves to fish and is good at it. I'm sure he'd appreciate just a wee bit more info on my machine!