The factory does it on purpose.
And it's getting worse.
Consider my Father's Nissan Altima. At around 65K miles, the silly thing refused to shift from park into drive. Dad, not being the clueless sort, found the safety switch over-ride and got himself and Mom home safely. I wandered over the following weekend to figure out what was wrong with the thing. After a little simple troubleshooting, it turned out to be a microswitch that (combined with another switch on the brake) applied power to a solenoid that moved a lever that allowed shifting out of park. A 49 cent part.
Except Nissan won't sell me one. They insist on selling the complete shifter assembly "because the old one might be worn out and a safety hazard". At somewhere north of $600+labor. So I pulled the microswitch, with the intent of finding one that I could install in its place. When I got it out, I demonstrated my circuit tester to my youngest niece (she was 6 at the time, and an aspiring mechanic), only to discover that the fscking thing worked normally out of the car!
We got to looking at the problem, and discovered that the metal actuator arm on the microswitch had become bent with wear. I bent it back and re-installed it in the car. Result: working car and successful unexpected lesson for my niece. Win-win.
It went out again 70K miles later. I re-bent the part, taking note that there was no appreciable wear on any of the other shifter components after 135K miles ... the shifter assembly that the Stealer insisted had to be replaced, mind you.
Total cost to my parents: $0/parts, $0/labor, and 2 mom-cooked meals for the wife and I. The Stealer would have charged just about $1,600 for the two repairs ... and they tell me this is NORMAL for modern cars!
A quick glance at TehIntraWebTubes suggests that this is a generic problem with the Altima, and has been for years. Nissan is well aware of it, and could have fixed it permanently over a decade ago at ZERO ADDED COST OF PRODUCTION! Now ask me why I'm sticking to 1970ish and earlier restorations. At least the old car set is (mostly) honest.