Am I buying Yugo parts?

Window switch (from dealer) broken, 14 months old.
Fuel filler neck (from dealer) flap doesn't spring closed anymore, 17 months old.

Then there were the 3 alternators (via Bosch) that I went through before finding one that worked.

What's going on here?

 

The further away from the engine/suspension/brakes, the lower Porsche's quality/engineering, I've always thought...

(...and that's seemingly one cliff of a drop-off for some pieces.)

 

My experience has been better. I went through 3 aftermarket oil pressure senders that didn't work before I bought an OE one from Porsche that works beautifully. However I've found that if a part number starts with 964, that part is very expensive and if it's something used for a number of P-cars and the part number starts with a 911, it's no so a bad. e.g. a 964 specific heat exchanger hose is £80 while an door window seal which is used for a number of 911s is only £5!