That is a result of the detail shops. Detailers, including those at the dealerships, use "wheel acid" to clean the wheels. It immediately cleans the wheel inside and out with very little effort. You'll see it at any car wash (and at the dealer) in a 5-gallon bucket with a push-broom size brush and handle. It does an amazing job but after the 15th-20th wash, you'll start to see the fading. Then eventually, the paint will fade, peel and corrosion will start. Mercedes used this for years in the 80s and all the "flat" wheels on the SELs and SLs were stripped of paint by their 5th birthday. This is why I use a mild dish soap and all of the wheels on all of my cars, even after 100s of thousands of miles are like new. AND, I live right on the ocean, where corrosion is the
#1 enemy.
Not to defend Maserati with any type of bias, but I'm curious, as a 2005 owner, what missed details you've noticed and what indicates poor assembly.
Keep in mind that your car was assembled using components (electronic and hardware) from various Ferrari cars of that era. For example, your firewall forward parts (windshield wiper assembly, etc.) is right off the 599, as is your entire steering column, cover, etc. Your mirrors are 612. Many buttons and electronic components are from 599, 612 and 430. Your brakes, suspension and power train are pure Ferrari bred and built. Your paint (assuming it is original) is straight Ferrari quality. From a sedan perspective, I equate it to Bentley/RR. Factory wet sanded with slight imperfections inside the door jams indicating hand finishing. All the body lines and gaps are perfect. The interior has incredible visibility and zero dash glare - a huge problem in many cars. Regardless, I can assure you that the factory in which your car was built wasn't composed of jack asses bumping into each other forgetting to tighten screws and paint wheels. Typical deficiencies in used QPs are generally a result of replaced parts and wear caused by various levels of neglect.
What I can say is that a performance car built to these standards, especially as a sedan, is entirely impractical and has almost zero demand in today's world. The 75 year old owners of Ferraris love to tinker with their cars and hit the open road but when it comes to taking the grand kids to church on Sunday, they don't feel like fooling with the eccentricities of Maserati. That's why you can't give these cars away.
The only way you (or I) can see value in these machines is knowing their pedigree and understanding that this technology and performance comes at a price for a reason. If Ferrari didn't understand this, then the Japanese would've put them out of business a long time ago.