Visors have always had a slightly ridiculous reputation, somewhere between a tennis court in 1997 and a golf dad who takes it far too seriously, and I get why. No crown means no hiding what your hair is doing, which is the whole problem and also, once you accept it, the whole point. I came round to them properly a couple of summers ago on a walk that turned out to be three hours longer than planned, and by the end my head was cool and my fringe was ruined and only one of those things bothered me.
Where a visor falls apart is pairing it with anything that already has volume up top, a big bun, a scarf, hair that needs covering rather than just shading. It wants hair pulled back and flat, or very short, otherwise you get this odd stacked look like you're wearing two hats. In the shop, check the band width before anything else, a narrow one digs in on longer wear and leaves a mark you can see hours later, and check how the closure sits at the back, because a plastic snap with sharp edges will catch on hair every single time you take it off. Have a proper look at the brim too, holding it up to a window is a good test, since a cheap one lets enough light through that you'll still be squinting by midafternoon. The difference between a visor that lasts and one that's bin fodder by August comes down to the band. A decent one has proper stitching that doesn't fray after a few sweaty wears, an adjustable strap with a buckle that actually holds rather than slowly loosening itself over a day out, and a brim with some real structure in it so it doesn't go soft and droopy after being squashed in a bag, which mine did within about three weeks, flat on top like a sad little pancake, because I'd bought the version with no stiffening in the brim at all and paid for it. Foam lining on the inside of the band helps too, it stops that greasy mark you get on cheaper ones after a hot walk.
This is a fair weather, outdoor job through and through, running, walking, anything on a boat, festivals, the school sports day where you're standing in direct sun for two hours pretending to care about the egg and spoon race. It has no business near an office, a dinner, or anywhere with air conditioning doing the cooling for you, because then it's just a strange plastic headband.
It solves exactly one problem, sun in your eyes, and solves nothing else. Your hair is on full display, your scalp gets no cover at all, and on a cold or overcast day it does precisely nothing for you.