I'm the designer of Kimini, a carbon-body tube frame mid-engine Mini that once appeared on the cover of GRM. Got it all done, enjoyed it a few years, but with all the challenges solved, got bored and sold it.
I then designed and built Midlana, a tube-frame "Lotus Seven". Got it all done, enjoyed it a few years, but with all the challenges solved, got bored, and... there were a few additional reason why I sold that one. The biggest was nickel and diming my way into having such an expensive drivetrain that I wasn't enjoying it on-track, fearing the potential repair costs (some may remember I popped the engine once catching up to a GT2. That was around $12K, and went a long way toward removing joy from driving it hard). Then there was also the waning enjoyment of driving it in our sucky traffic. When the overall enjoyment reached zero, I sold it.
I decided to replace it with a used Jaguar F-Type R, a car so beautiful that I'll blame that instead taking responsibility for buying it. Fast forward one year, and we realized that we never drive it... Why? Extremely little cargo space, which ruled out nearly all Costco runs, and most every other place since I always seemed to buy stuff too large, too long, too smelly, or too messy to put in the Jag, so we take the F150 truck, which sucks to park. About this time I was talking to an owner of a Tesla Model 3 Performance. She mentioned that her husband is extremely protective of it, always parking far from others, worrying about door dings, rock chips, and all the other stuff obsessive owners worry about. And then she said something that stuck in my head, saying that the car caused her anxiety... It was right then that I realized I have the same situation with the Jag. I worry about door dings, rock chips, and all the other stuff obsessive owners worry about. There was also not enjoying it in sucky traffic - just last week we drove down the coast, and had to idle along with everyone else at 17 mph with my 550 hp. But the big one, the one that really ate at me, was worrying about any future repair costs. The car never gave us any trouble, but it was the possibility of something expensive letting go that hovered over my head, reducing the enjoyment. (I worked in Field Support for 11 years where we'd take 24/7 shifts, carrying the "emergency phone" at all hours. The phone might not ring, but just knowing that it could, effectively ruined the entire week. My analogy was that it was as if a piano was hanging by a string over my head. It might not drop, but just knowing it's there caused a lot of stress.)
The biggest lesson I learned from this is: If you buy a used car that was very expensive when new, even though you didn't pay that, repair shops will treat you as if you had. An exotic headlight assembly is $4,000, and a used engine is $20K, regardless whether you paid $100K or $10K for the car. I should have realized that beforehand but didn't.
So, the Jag has been sold after only one year of ownership. Of all the cars I've owned, I sometimes miss my old Datsun 2000 Roadster; I loved driving it, it looked great, but was such a pain to work on that I don't miss it. For the Jag, it's a bit like that: I loved driving it - when the roads were open - but between that, the lack of cargo space, and my self-imposed dread of repairs, it just wasn't a good fit for me. Yes, I know full well I caused these "problems" myself, and that this all sounds like (is) a First-world Problem. But in the end, I bought a car inappropriate to our needs or lifestyles.
It's also tough to admit that I'm just not wealthy enough to not worry about owning certain cars. The Jag's beauty is a big reason to have it, but it turned out to be (potentially) too far toward the deep end of the money pool for my comfort.
I ended up with a spreadsheet of 26 replacement candidates. The requirements were: small/short, easy to park, good cargo space, and not so expensive that I'd worry about it. Overall length ruled out most, and various other factors ruled out all others save for one. I waited a while to see if I'd change my mind, but didn't, so now we own a Mazda CX-30, a small SUV sort of thing. I had to smile, realizing that I made it all the way to my 60s without ever owning a mommy-mobile, but finally caved into practicality. Probably the thing that surprises me most, however, is that I'm okay with that, coming to terms with what's the best fit for us. It's very nice, very comfortable, well built, and the sports car guy inside me isn't entirely dead, as we got the turbo.