The Mini lives outside and is my every day car. It's used throughout the year and isn't tucked away in a garage for the winter months so obviously some parts will age faster under these conditions. However, this is the way I've always treated cars and the Audis and Fords I've owned over the years have been happy to live outside with the very minimum of maintenance.
To list the more obvious faults that I have had with new parts:
The water pump started squealing after 12 months and needs a few drops of oil once a fortnight.
The super dooper two core radiator sprung a leak last month and needed replacing.
The radiator cap wouldn't hold it's stated pressure.
The gaskets between the lenses and the chromed bodies of the rear lights are too small and it's impossible to stop them leaking.
The stainless steel front indicator surrounds are badly rusting
The kevlar lined top and bottom radiator hoses are cracking and will need replacing soon.
Both gaiters that were supplied pre-fitted to the new quick rack rotted out within 9 months.
The windscreen rubber is beginning to crack.
Both CV boots are beginning to show cracks.
Two front tie rod rubbers collapsed within a year.
In addition to the faults that have become apparent over time I was supplied with two sets of front hub swivel joints that were so badly finished they were just plain dangerous. The small dome hadn't been ground down, but more importantly the domed nut would lock solid on the upper dome when the two were put together on the bench.

Now I might not be the best or fastest mechanic in the world but I do know how to repair and fix most things on a Mini, and having worked on all the cars I've had for the last 30 years I know how long parts should, or rather, can last. All the modern cars I've owned have been 10-15 years old and I've tended to keep them for a number of years. CV boots, rack gators and window rubbers are pretty much a fit and forget item for modern cars. I've never had to replace a rack gator or CV boot on any car I've owned apart from my Minis, but it looks like this is now going to be an annual occurrence. The bad water pump and failed radiator I can put down to bad luck, but the poor quality of the rubber components for Minis is simply cost cutting.
I know original Leyland and Rover rubber parts are supposed to be better quality and I have a pair of Unipart boxed CV boots in the loft that are at least 15 years old. I'll be fitting these next spring if the currently fitted new boots last that long. If retailers find it difficult to source reasonable quality components can't they at least give us an indication of quality, particularly for rubber parts? I don't expect to see a description to include the statement "This quality of this part is b****y awful and it won't last a year" but perhaps a "budget" tag would give us an indication of the quality.
Even better than a "budget" tag, if a supplier could give us a choice between cheap 'n cheerful or OEM quality rubber parts I'd be very happy. This shouldn't be impossible, after all, the materials exist that allow a CV boot to last 15 years. As far as I can see it only requires the the component manufacturer buy the correct rubber, presumably at an increased cost, and make the long life component. Given the choice of a rack gator that will last a year (if I'm lucky), or a German OEM quality gator that lasts 10-15 years and 200,000 miles I know which I would buy, even at 3 or 4 times the price.
It was all better in the past when things were properly made and the summers were warm and beer was cheep etc. etc. etc...........

Whinge over.