2 every day bikes, one for climbing and the other as backup in case #1 has mechanical issues
1 fendered and heavy rain bike
1 mtb for trails
1 gorgeous steel bike that I just can’t make myself part with.

I could lose two bike but don’t feel the need.

- Carbon road go-fast bike, Di2, narrow tires
- Alu gravel bike
- Lugged steel touring bike
- Alu hard tail mountain bike, I dont really need this bike, since I got the
- Carbon full suspension mt. bike.

I use every bike for different things

I'll own as many bikes as I want and wear whatever eyewear I choose.

@OP because there are just too many X's you do know you are on a bike forum correct? Would you go to the guitar forum and ask why do you have so many different guitars?

Bike are awesome but they all do different things. I wouldn't take my road bike mountain biking and vice versa. Plus bikes are awesome, having just one is boring and unless that is truly all you can afford and have space for more bikes the merrier.

Though I am at the point of thinning what I have just to stuff that really brings me the most joy and get more riding. However if I had the budget and the spacing I want I would probably add a bike or two but they would be full custom built titanium bikes with really nice parts on it

Non-responsive.

Life would be too boring with only a couple bikes. Let's see:

1 carbon road bike that is my go-to bike.
1 steel road bike that is set up on the trainer.
1 carbon gravel bike that gets ridden regularly on its intended terrain.
1 carbon FS XC bike, I usually save it for racing.
1 carbon enduro bike, I use it for the uber-technical hike-a-bike terrain up here in the mountains.

So 5 bikes, I want even more. I do have a pretty nice 25 year old Cannondale CAAD 5 that I never ride, but it's too cool to part with. Full Dura-ace and painted in the Saeco team colors. I could justify adding another gravel bike...gravel riding is a spectrum and not just one style of terrain. I'm also going to be building a lightweight carbon road bike up as my "climbing" bike, to compliment my main road bike.

Basso Ascot. Primo ride with a double, great for rides with no climbs in excess of 5%

Lemond Buenos Aires. Another Primo ride but with a triple to help this old man get up steep hills but still havel closely spaced gears.

Schwinn Tempo. It's tre colori, gotta have tre colori. Also has BMX pedals on it, kinda nice to have a road bike with flat pedals sometimes.

Olde Legnano. L'eroica ready, just in case.

MB-3. Dad's old bike. Plus everyone should have a lugged steel MTB.

Carbon hardtail. Life's too short to ride heavy bikes up steep hills. This is also my flatbar gravel bike.

Ellsworth Joker, full suspension for stuff too rough for a hardtail .

Ritchey Commando fat bike. I've got 3 wheelsets for this one. Used for snow rides, dirt touring, etc.

Kent Glendale single-speed. Beater bike, grocery getter, whathaveyou

There are a couple more, but that covers most use cases. If I lived in a place with UCI-sanctioned CX races I'd probably get a CX bike too.

Almost forgot about the tandem, for tandeming

I guess I have six.

Soma Fog Cutter steel frame 2x11 hydro disc with 700c and 650b wheelset. Fenders, dyno lights.
Focus Mares CX 2x10. Decent fender mounts. Race wheelset and commuter wheelset.
Trek Domane SL6 carbon that's my new rando bike. Dyno lights, fenders, Selle Anatomica saddle.
Detroit Bikes fixie, set up for commuting with fenders and battery lights.
Trek Roscoe hardtail.
Volae Team high racer recumbent. Two seats: carbon and mesh. Dynohub, but lights robbed for the Domane.

So here's the thought:
Sell the 'bent, keeping the dyno hub.
Sell the MTB. I don't MTB; not sure what I was thinking.
Sell the Focus. I've proven I'm no CX racer.

Keeping:

Trek as my rando bike and sport bike. PBP in a week!
Fog Cutter for dirt, gravel, knock around bike. Backup commuter, backup rando.
Fixie as primary commuter and dabbling into fixed rando. Use the 'bent dyno to build up a new front wheel, and add dyno lighting.

Of course that leaves blank spaces in my garage, and a complete lack of a flat-bar bike

Forgot about the unicycle. muni, actually. Not technically a bike though, so doesn't count.

I have 7, 8 if you count the parts bike. Why? #1 reason is they were cheap..

1 Thermoplastic carbon full suspension bike - Downhill MTB Bike -GT
1 Aluminum full suspension bike - Cross Country MTB Bike -KHS
1 Aluminum front suspension bike - All purpose Hardtail MTB -Trek
1 Aluminum/ChroMoly rigid bike - Mixed frame material MTB -Fisher
1 Aluminum rigid bike - Elevated Chainstay MTB -Revolution
1 ChroMoly rigid bike - Rigid MTB -Fisher
1 ChroMoly rigid bike - Road bike -Raleigh
1 Chromoly rigid bike - Complete parts bike -Diamondback

See...not one is the same..at least that's what I tell my wife

That's a good question. You should put together a 20-bike stable to thoroughly analyze the matter.

I've got over a dozen. I've got to have a clunker crap heap I can lock up and leave around London without worry of it it being stolen or vandalized.

I've got to have a MTB for riding off road and in snow.

But the rest of them are all basically the same, road bikes from the 80's and 90's with cool paint jobs that I buy as a frame and then build up. I really enjoy the thrill of sourcing each and every part and turning a pile of parts into a functioning and beautiful thing. This makes each bike bespoke and unique. And then there was the 'I've never ridden a carbon or ti bike, lets try one of those....'

Buying a new off the shelf bike to me seems like missing out on half the fun of a new build project. Also new bikes are ridiculously expensive these days, and to be honest I find modern bikes look a bit boring, samey, soulless and lacking in character, so building up something unique for a lot less money is a no brainer for me. I don't think I'll ever buy a new bike again.

So every year I like to have new project to work on. Maybe as a result of the extra time and effort I put into building a bike I get more sentimental than if I'd just gone into a shop and bought one. And after riding it and having experienced great rides together I definitely develop an attachment, so getting it rid of it after all that seems like selling one of your own children.

I find a new project and bike tinkering is therapeutic, and 100% helped my mental health during the covid lockdowns. I have an addictive and slightly obsessive personality, so of all the vices that could have gripped me, I feel bikes is definitely one of the healthiest options out there, so I am in a happy place.

However I am now at critical mass, there is no more room at the Inn, my small apartment is full of bikes so I cannot take on any more projects until there are some outgoings, its going to be an emotional wrench but some of the children are going to have to be put up for adoption.

Why not have many bikes ? Indeed . Because Existence Exists, and Existence Existing is Infinite, including bicycles. Asking why is like looking at the forest and asking "why so many trees ?". Nothing Exists apart from Existence Existing.

I have loved bikes for 70 years. Now long retired I have 24 but 6 are for the kids and grandkids when they visit. I am fortunate to have a hanger w/o a plane so plenty of room. I have to do things like keep the tires treated with Aerospace 303 or I would never wear them out but as a retired mechanical engineer with maintenance experience I love the time, it is beyond just a hobby. I take great pleasure in my time in the saddle, the care and keeping, the hours of tinkering to improve performance/pleasure.
add spice to life. Life will feel like a chore and tedious process without them. But, on the other hand, they both make you feel happy and fulfilled and accomplish specific roles in your life. Any activity can become a hobby or passion; it depends on how much time and emotional investment you are willing to make for something. A hobby can turn into a passion and vice-versa. How you want to treat an activity will dictate whether it becomes a hobby or a passion for you. If you only want to do something to relax and have fun, then it should stay as a hobby. However, if you're going to get serious and become better at doing something and plan to turn it into a career, it will be better to become a passion.

"Variety’s the very spice of life,
That gives it all its flavour."
-William Cowper

I have different bikes for different rides.
A couple are dupes, but most are different.
Single speed drop bar - Raleigh Gran Sport
Single speed flat bar - Coaster brake hybrid conversion
2 speed SRAM Automatix flat bar - Bridgestone "mixte"
5 speed IGH Cruiser - Gazelle Opafiets
8 speed IGh Market bike - Raleigh Grandier Sportier
9 speed All-road - Maxwell Hybrid that has been modified to flat bar
2x7 Geoffery Butler Drop Bar road
2x9 Witcomb Drop bar road bike with front and rear bags
2x10 Fuji Drop Bar road bike
3x10 Centurion Pro-tour flat bar touring
others for fun

Not actually a silly question. Most of us have probably asked ourselves the same thing, especially every time we bring a new one home.

Everyone's got a different reason (and the numbers 10-20 are certainly arbitrary) but for me, it just sort of crept up on me. Obviously you need a bike for each type of riding you want to do, but as someone else pointed out, even bikes in the same "category" can be dramatically different. It's fun to ride different bikes and experience the different personalities and characteristics of each. And if you've built or restored them yourself, you sort of become attached.

I've often thought about selling one bike or another, when I'm looking at them all in the garage and realize that I have a lot of redundancy. But then I take the bike out on the road and think "Man, I can't sell this." Plus it gives you flexibility. I bought an indoor trainer and didn't have to worry about having a bike to put on it. I chose the Rockhopper and still have two other MTBs that serve me well as gravel bikes. Also when guests come and visit, between my wife and I we have bicycles for everyone.

I think space is probably the limiting factor for most people. But if you have the room, there's little reason to get rid of a bike that you love just because you got a new one.

No matter the number, if someone has bicycles that they display but don't ever ride, that's a collector. You're choosing bikes for a different reason than their ride characteristics. Right now I'm trying to resist the temptation to buy a 1973 Schwinn World Voyageur in Sunset Orange, just because it's so pretty. I'm sure that I'd ride it a few times just for fun and nostalgia, but it's never going to be the bike I choose to ride over some of my others on a normal basis. I would find a place to put it on display, and now I'm a collector.

If you a have large number of bikes that are neither ridden nor being displayed as a collectible, that's a hoarder.

I've thought about keeping a few of my flips and growing the stable, however, I also enjoy when my labor and sweat literally pays off and buyers appreciate it.

It's in the DNA. Hunter/gatherer, scavenger, hoarder. It can be channeled a number of ways from massively selective to rooms filled to the ceiling with debris.

Best of luck

This is the most wolfchild response of all time.

You make an over the top declaration that judges others(more than 5 bikes is hoarding) and you come to that conclusion because you personally would stop at 5, therefore its hoarding above 5.
Classic wolf.

I have a 2250 office/warehouse so space is not a problem. Double digits bike wise. Why? Well, many years ago, I had to quit the team/ball related sports because of Father Time and injuries. So, I became a cyclist/endurance athlete. I started with a hybrid, then got a C&V bike from a Goodwill store and brought it back to life. I really enjoyed that experience. Then I started doing the ride listed below. Each year, I would find an an old steel roadie, fix it up, take 1 or 2 shakedown rides and do that ride on it. Sometimes no shakedown rides. It was/is the ultimate blind test ride. I really enjoy that experience. Never been disappointed with a bike yet. I had to skip the ride this year. I couldn't get the the weekend worked out. I still have this year's bike in que for next year. At this point in my life I don't give a rat's ass about how fast I ride or if I'm improving. All of my rides are recorded by a watch, but only for consumables tracking. I never look at the results. I just enjoy riding bikes, watching the world go by and listening to the sounds around me. Call me Ferdinand the Bull if you want to. If all you're worried about is your performance/results, you can get that fix in other ways that are cheaper/less time consuming. Tomorrow is promised to no one. Just get out and do it, whatever "it" is.

https://www.ymcacva.org/storming-thunder-ridge

I never planned to accumulate 5 bikes. Here's how it happened: I took a little while to decide what kind of riding I really want to do and find a bike that's well suited to it. Along the way, I somehow collected others. I don't usually buy new, but build them up and customize them to my liking. This process causes me to form an attachment to them, and then I don't want to get rid of them. If I were to sell any of the bikes in my current fleet, I probably could not get a price close to what I've spent on it, or what it's worth to me. Even if I could get past that, I would have a hard time deciding which one(s) to sell. For what it's worth, I've had 4 or 5 others along the way, and sold them. When I find one bike has a lot of overlap with others, or it doesn't suit me well, I offer it for sale. I wouldn't say I took a bath on any of them, financially. But nor did I make money on any.

I ride all 5 of my bikes, but some more than others. I could probably get rid of one or two and not miss them. There are at least two that I'm so attached to, I don't think I could ever get rid of them. I'm 53, and I hope to ride for at least another 20 years. Unless something changes, I'll probably own a few of my current bikes for that long.

The short answer is that I have several bikes because I really like them, they make me happy, and I get good use out of them.

Cars are another matter. Recently, my family owned 5 or 6 cars. How we got there is kind of a long story. They did not make me happy. They cost a LOT of money to maintain, register, and insure. They take up a lot of space at our home. They're a cause of many headaches. I'm now down to four, and plan to get rid of one more before long.

I have one because I don't need two. Remember Then Came Bronson? It was his everyday mode of transportation, and he could remove the fenders and compete in hill climbs.

Nostalgia. Pure and simple.

Everytime I look at my old rides it reminds me of the great times I had riding them. Fast centuries. Suffering in heat and rain and cold. And also of when I was (much) younger.

Besides, what is a 40 year old Raleigh Pro worth? Next to nothing. But a lot to me.

Someday, when we move to another city or downsize, I will have to thin the herd. It will be a sad day.

N+1=infinity
Not sure of the issue, if a person has 3 or 30 bikes - so be it ?