Crappy Syncro shifting when compared to other indexing systems.
Delta brakes
Non compatibility on weird things like shifter cables.
Previously mentioned chain system with guide pin and peening with specialized tools
Slow adoption of double pivot brakes.
EPS (need I say more)
Crazy pricing
G3 Lacing although looks cool, harsh ride, difficult to true.
Poor support network and parts availability, factory supported gray market.
Ridiculous attempt at mountain bike group.
Carbon crank set failures.
Ego power shifter, internal durability, G spring failure, etc.
Heavy shifter feel, especially when compared to Dura Ace
Ulta-Torque crankset weirdness, Record and Super Record had opposite threading.
Ceramic bearing poor durability.
Very limited lifespan on top tier cassettes

Generally, the public did not accept the product. The attempt to market themselves as the ultimate component manufacturer and charged as such yet the products were not better performing in anyway. Given what people will spend on perceived top-tier cycling products they were unwilling to do so for Campagnolo.

The majority of what you listed are just differences between Campy and Shimano. The others are either minor issues (that are easily dealt with), or they're simply untrue.

In many cases it was Shimano who created different standards from Campagnolo's pre-existing standards. I consider it a plus that Campy preferred to maintain manufacturing in higher labor cost Italy rather than moving production in order to compete with Asian wage standards. Sad that the most recent Ultra-torque bearings I bought were manufactured in China.

I think they had issues with the early Delta brakes and I think a crank issue in the 70s on a few track cranks maybe? I can't think of a lot of Campagnolo issues and even if so other brands will beat them heavily. I think SRAM in their shorter history has had more issues and Shimano in their similar length of time has also had a lot of issues but nobody is questioning them? I always find it funny when people go after Campagnolo when Shimano has a massive active recall for cranks right now.

People love to hate groupsets they haven't ridden. It is always funny. Campy is expensive (what about SRAM Red AXS or Dura-Ace...), someone said Campy doesn't shift well so it must be true...

The issue is the products were not attractive to the consumer for numerous reasons but not limited to those I listed. Average cyclist, passionate enthusiasts, amateur racers and a majority of poseurs chose not to ride Campagnolo. They effectively brought nothing to the table.

As previously mentioned, I exclusively rode Campagnolo for almost a decade, then on a Cycling vacation in the Pyrenees I needed a replacement cassette which was very difficult to source, even in a very popular cycling destination (Argeles Gazost) yet Shimano availability was no problem. It was then I questioned why I was riding Campagnolo in the first place, I realized it was only for the prestige and bragging rights not performance in anyway. Now all the bikes in my household are running either Dura Ace or GRX. I see no compelling case why anyone would choose Campagnolo. However, there are numerous reasons why not.

These are not minor issues sadly, Campy was always more expensive than Shimano and not necessarily better. Campy failed with their Euclid group in mountain biking market whereas Shimano succeed and remains today way ahead of SRAM regarding MTB and Road transmission in terms of sales.The G3 spoke lacing isn't necessarily better than the Rolf double spaired spokes or than a traditional spoked wheel , their older Ventos, Zonda and Scirocco while being nice wheels , had average quality hubs that couldn't match Mavic or Zipp bearings hub quality and their wheels were prone to cracking.The campy dual pivot brakes were never a match to their Shimano double pivot brakes counterparts. I have a rare Raleigh made of Reynolds 753 with C Record and Delta brakes, while the Delta brakes might be nice, they were and are a far cry in terms if stopping power compared to the first generation of Dura Ace dual pivot brakes. The carbon crankset failures have happened and I recall my bike tech telling le the horror stories about the Ego power shifter, internal durability, G spring failure and the clunky heavy shifter feel, especially when compared to Dura Ace. Also he mentionned the Ulta-Torque crankset weirdness, but also the ceramic bearings poor durability. When you pay top dollar for a transmission and that failure is recurring often , you can ask yourself of what kind of so called high quality product is the result from this strategy.

I have Delta brakes with a C Record group on my Reynolds 753 Raleigh but those are not the brakes I would rely on in a wet rainy ride. The other issues with Campy are several such as the ergo power shifter, internal durability, G spring failure, etc, a much heavier and clunkier shifter feel, especially when compared to Dura Ace, the Ceramic bearing poor durability, the very limited top tier cassettes durability and carbon crank set failures. Shimano has also to be blamed because they dropped forged cranks for bonded ones even though if it is not the same quality, yes forged cranks were more durable and much more expensive to make. The FC 7800 Dura Ace crankset will never split and never break unlike the bonded ones. Maybe not everyone is interested into having an expensive but finnicky and problematic transmission.

Every product line has reasons that make it unattractive to some consumers. But, that's mostly a case of personal preference, and it certainly doesn't qualify as "countless failures."

There's too much to unpack in this, so I won't address it all. 1) You just stated "The G3 spoke lacing isn't necessarily better than the Rolf double paired spokes or than a traditional spoked wheel" as evidence that Campy is inferior. 2) You're comparing brake performance from nearly 35 years ago. 3) You're citing Campy crank failures when Shimano has recently had a huge crank failure issue. 4) Ultra-torque weirdness? They have a different design that works very well. What's the issue?

Yes you have a point however from a manufacturer and retailer of a product, if it does not sell and does not gain market acceptance, it is a failure.

Selling less than Shimano does not make Campagnolo a failure. (If selling less than the dominant manufacturer defines failure, then the vast majority of businesses in the world are failures.)

Hmm.

In its first year in the pro peloton, Campagnolo 12 speed won the '19 Spain National Championship under Valverde, Alaphilippe won the '19 Strade Bianche, and Carapaz won Giro d'Italia. Pogacar won Tour de France twice, in '20 and '21, on Campagnolo 12 speed.

Hard to see how you can say it was "far behind" in overall performance.

Citing tour use, or even tour success, does not prove a product is a leader in performance.
I think you know this and could easily come up with examples where products are used and succeeded with, that aren't leaders in performance.

I am not claiming Campy was far behind, to be clear. I am only saying tour use and success isn't a great barometer for determining if a product is a performance leader.

That someone would cite G3 lacing, a feature that has been on the market more than 20 years, as a failure, clearly suggests they're working with a definition of failure that's very non-normative.

It also runs counter to the general acceptance of Campagnolo wheels as very high quality.

Campagnolo was the first in the world to introduce a 12 speed road groupset, three years ahead of Shimano. It was good enough to win the Tour de France, Giro d'Italia, and other prestigious races, yet some are saying Campagnolo 12 speed was behind... Wacky, right? First to market, first over the finish, but behind. Yeah, sure you're right...

All of us want Campagnolo to succeed. Nobody cheering their failure here; just pointing out reasons for their demise.
However, a good number almost fanatically defend them. Their slow death began ages ago and not from a few BF members buying other components.
When I re-upped into cycling around '93, I did not care for the thumb shifter and pricing. Sure made it easy to select Dura Ace.
Over the years, I found a few pieces to my liking, including wonderful Bora Ultra CF wheels (Shimano-compatible), CF seatposts, and nice clothing.

Quoting Pro Tour results is disingenuous because of sponsorship considerations. It’s not like Campagnolo is a boutique premium brand with solid market acceptance but limited sales due to its pricing and exclusivity such as Ferrari. People did not see the value because it wasn’t that good when compared to its competitors. As mentioned earlier, no segment of the cycling community were enthusiastic supporters of Campagnolo. It just didn’t sell nor was it desired.

Yeah, it's devolved into just a pig-pile of know-nothing haters! Campagnolo introduced the first aero system wheel set by a component manufacturer with the Shamal in '93, a wheel set that went on in their first pro season to win both the Tour de France under Indurain and the Giro d'Italia. In 2008, Campagnolo introduced CULT ceramic bearing wheelsets. Shimano ceramic bearings? None that I know of. Campagnolo introduced their first full carbon fiber rim wheel set, the Bora, in 1994, seven years before Shimano offered one.

Campagnolo's history of innovation is unequaled.

Yes but the Deltas weren't great but they were more designed for looks and besides most of the brakes of that period I wouldn't rely on in the rain. I have yet to hear about cassette and bearing durability but I would wonder how much less durable they would be compared to SRAM or Shimano and how often that happened. I have a friend who had 9 speed ergopower shifters that were heavily ridden probably about 10 thousand miles per year and eventually after 15 years or so needed to be rebuilt and that bike was not maintained super well and saw some crazy riding. However that is anecdotal and doesn't mean much but I haven't seen or heard of a lot of Campagnolo failures and I think compared to the other 2 they are pretty low.

The mere fact that Campy shifters can be rebuilt (as opposed to Shimano's STIs, which would be thrown away) is a huge plus.

Innovation without perceived performance gains is nothing but marketing. Ever since Nuovo Record, when they relied on shop bro’s promising superior, build quality and performance when in reality, Shimano and Suntour were innovating at a rapid pace, quickly out pacing Campagnolo. People were just tired of being ripped off and abandoned the brand. You mentioned CULT bearings and they failed prematurely and were ridiculously expensive to replace, ask me how I know.

I reiterate there is effectively no part of the cycling community which enthusiastically supports and desires the product

One of my best buds was a triathlete and he always raced with dura ace, first in 1992 with Dura Ace 7410 until 2001, he must have changed bottom bracket 6 times, then he upgraded to Dura Ace 7700 from 2001 to 2005 , never had probs and lastly upgraded to Dura Ace 7800 in 2005 until now and never had any probs , he changed of bottom brackets 7 times and the transmission is always so reliable. He also has changed of cassette 5 times . I raced with 105sc then switched to Ultegra 6500/Dura Ace 7700 but never had any issues. I prefer STIs with the external cables which are working well for me in any condition.

That urban myth should’ve died off decades ago. Parts availability is ridiculously difficult, expensive and no bike shop was willing to do the work.

I find it funny that people are attempting to debate whether Campagnolo's shortcomings are legitimate, whereas in reality the market and customers have already spoken and made a definitive judgement.

I mean if they were actually competitive, then why is the company failing?

It's not like Campagnolo is behind Shimano by just a little bit. As of last year (2024), Campagnolo's sales are just 1/20th of Shimano's sales. (SRAM sold about half as much as Shimano).

So it's Shimano first, SRAM a distant second, and Campagnolo barely exists.