Mac Loc: Pittsburgh, Philadelphia now Hernando Co. Fl.

NEED? Of course not. All you NEED is a lens, any lens.
For a while I used mostly zooms, but I found zooms were making me lazy. Instead of looking at a subject from different perspectives and angles to find the best composition, I would just use the zoom to fill the frame and that would be it. I went back to using primes to force myself to slow down and consider the best composition.
I own some zooms, they have their use, but I prefer primes. Not for sharpness (sharpness is overrated), but I do mostly street/documentary photography where a lens with a shorter physical length is more advantageous.
To each his own. Use what is best for you.

User ID

List them ? ROTFLMFAO !!! How many times have you read "War and Peace" cover to cover ? Never ? Okay then, howbout the Manhattan yellow pages ?

bwana Loc: Bergen, Alberta, Canada

No

bwa

jackpinoh Loc: Kettering, OH 45419

Prime lenses made more sense for DSLRs because you can only correct front-focus or back-focus issues at a single focal length for each lens. Mirrorless cameras don't have front- and back-focus problems, so they are able to focus at any focal length on a zoom lens. Also, lens technology has improved because the lens elements can be moved closer to the image plane on a mirrorless camera and because the higher pixel counts in modern mirrorless cameras forced new and improved lens designs.

Canisdirus

Which is better is not dependent upon intended usage.

Prime perform better...dollar for dollar.

Fredrick Loc: Former NYC, now San Francisco Bay Area

To specifically address your question, I have plenty of fixed primes, but find myself using my 24-120mm lens 95+% of the time. Thoroughly pleased with the results.

TriX Loc: Raleigh, NC

I recently had occasion to test 3 Fuji zooms (16-80, 50-140 and 70-300), all set to 80mm and wide open, against the 90 f2 also wide open. Even though the 90 was 1-2 stops faster, it was sharper and had noticeably higher contrast, including that of the 50-140 “red badge” zoom. It was the better contrast that was so noticeable.

So yes, I wouldn’t be without my primes - smaller, lighter, faster and sharper are some of the reasons. I have 3 Fuji zooms and 3 primes and 4 Canon zooms and 3 primes (almost all Ls), and my two favorite lenses of the bunch are the Canon 135 f2L and the Fuji 90 f2.

MountainDave

I have more primes than zooms but my EF 24-70 2.8L II is my workhorse. I do sometimes wonder why I have primes in that range. However, I recently sold my 16-35. It was too heavy to haul with the 24-70. Now I have a RF 16 2.8 which I can stick in my pocket. The strategy works great! Sometimes I take my RF 70-200 4L hiking and can stick a nifty fifty in my pocket. I have no regrets about my longer primes (85 1.8, 100 2.8, 135 1.8 & 300 2.8) When I wish to create special images, I reach for one of those.

I agree with another poster mentioning that zooms can make you lazy. When I'm using primes, I do concentrate more on my position and composition.

CHG_CANON Loc: the Windy City

Still shooting DSLRs, I like to walk around with the 16-35 f/4L IS and the nifty-fifty 50 f/1.8 in my pocket. With deep shorts pockets, I can swap the lenses, such as touring someplace both indoor and outdoor.

MJPerini

Fast Primes used to be essential for some types of Photography, they were faster and sharper than most available zooms and film was relatively slow. Now the premium zooms from most manufacturers can be just as sharp as primes and often nearly as fast. Image quality at ISO 1600 (and higher) is now very high. So there are fewer reasons to 'Have to have' a fast prime for THOSE reasons.
But there are still lots of reasons that many people choose them. We can shoot in 'even lower light' and in bright light, one of the benefits of prime lenses -(especially a single one or a small set of discrete focal lengths) that is often cited by folks who like them, is learning to 'see' the field of view before you raise the camera to your eye.
Lenses like a 35mm f/2 are often mentioned. The more you use the lens the more you bond with it, and your pictures get better. There are lots of very famous photographers who did just that.
Some primes can have a certain 'look' - Canon's 85mm f/1.2 comes to mind.
Remember the 'Exercise' One Camera, one Lens, one film, One year' ? It taught a lot of people to be better photographers. But if you did it (I did) for better or worse, it left an impression (some might say prejudice) that stays with you.

If you shoot a broad array of subjects, that approach is not practical, or you may just think it is dumb, so everyone should do what makes sense to them.

Personally, I started that way (Nikon) 35/2 50/1.4, 105/2.5, with the 35 getting most use by far. Then I moved to Commercial Photography and needed a pile of lenses just in case, but I always has a camera with a 35 on it.
When I moved to Digital that changed a bit. I switch he'd to Canon and their latest generation of mid range zooms are really great. I use a 24-70 like 2 prime lenses mostly 24 OR 70 ---I frame the picture in my head with the camera with the camera still dangling in my right hand. I know what 24 'looks like' and what 70 looks like so I shoot 80-90% of pictures (with that lens) at one or the other. As I am raising the camera to my eye I flip the zoom ring to one extreme or the other before I frame & shoot.
I'm not suggesting anyone else should do that, but it works for me--especially for pictures of people, I can make eye contact until the last moment.
So, for me at least, the "prime mindset" means more than single focal length.

nealbralley Loc: Kansas

Primes still have their place as you validly mention above, but not everyone may have a need for primes! It is a question of what do you need, and of course, what do you want!

JeffinMass Loc: MA

In my opinion and I have been taking pictures since the dinosaurs the Prime Lenses will always be sharper than the zooms. Yes you can always "fix" the sharpness in Lightroom/Photoshop. That said the original image will always be sharper and the usually have fixed apertures.

wdross Loc: Castle Rock, Colorado

Required needs and wants determine whether or not a sharp prime is more desirable over a sharp zoom. Yes, primes are still slightly sharper and faster than a zoom that includes that prime length in it's zoom range. This is where your needs and wants come in. One case in point: You are constantly shooting portraits at a specific focal length and needing a very narrow depth of field. I would buy that prime at that specific focal length with the widest open aperture. If I shoot very few portraits at whatever focal length and whatever aperture for the lighting, then why buy a prime when a sharp zoom will cover the few portraits and everything else. And it doesn't just have to be portraits. If a specific focal length and open aperture is needed for what one shoots, then a prime that meets those needs is more advisable than a sharp zoom covering that focal length.

Again, it always comes down to needs and wants.

TheShoe Loc: Lacey, WA

mwsilvers Loc: Central New Jersey

Generally I would agree that few people need prime lenses, but many of us still prefer using them. Prime lenses are still the preferred lens type for many street photographers and are extremely useful in very low light indoor scenarios. I currently shoot almost exclusively with fast manual focus prime lenses between 10mm and 50mm with a maximum aperture of f/1.2 to f/1.4 for most of them. My lenses are all metal and glass with impressive builds and are tiny and light. Perfect for the street and very dark museums and dark historical venues. also great for isolating subject from background. Used on my small Nikon Z mount body the combo virtually disappears in my hands when I'm out and about, and my subjects mostly never even realize I am shooting them. I only shoot static scenes. No sports or wildlife. Not suggesting them for everyone, but they are the perfect, and preferred lens solution for me. One of the things I prefer about prime lenses is that limited framing options forces you to view things differently and often results in images that are very different from those made with zoom lenses.

Additionally, the number of people using their cell phones as a primarily or secondary camera these days continues to grow. Basically, cell phone camera uses only primes lenses, often three different ones for wide angle, "normal" and short telephoto. Any "zooming" is electronic not optical.