I have owned three BMW R1200GS'. They all have been troublesome. Just about tolerable when still covered by the warranty but totally unreasonable when not. A US survey of the 10 major manufacturers put BMW, unsurprisingly, at 9th.
It's important never to confuse a quality/prestigious product with reliability. After all it's generally accepted that Mercedes Benz cars are considerably more troublesome than Toyota!
Major things that have gone wrong -
Cruise control switch replaced (4 times on two bikes)
Rear shock failing on two bikes. The last one would have cost £2000 out of warranty.
Two new master cylinder.
Gearbox seal replacement, requiring the rear of the bike to be removed.
By comparison in the nineties and 0s I owned four Honda VFR750/800s. Did well over 100,000 miles on them and only two things went wrong. A loose bolt under the seat and a rear shock that had a oil leak. That's it!!!
There is a moral here, which sadly I have taken far too long to take on board.
This is not the type of thread you probably expect on a BMW forum but I feel honour bound to share my experience but I guess it will be removed fairly quickly.
Possible reasons for your problems are:
Cruise control switch replaced (4 times on two bikes) - You are becoming more and more clumsy
Rear shock failing on two bikes. The last one would have cost £2000 out of warranty. - You are becoming overweight
Two new master cylinder. - You do not know how to brake properly
Gearbox seal replacement, requiring the rear of the bike to be removed. - You do not know how to shift gears properly.
But seriously, here is my 2 cents,
BMW products are different from say, Toyota or Honda in that they are more performance oriented. Honda could have its six-cylinder engine produce much more power. They decided they want reliability instead. It is like that with every other motorcycle part. Every time one pushes things to the limit, reliability suffers.
Plus I am not sure if in BMW they have serious "zero defect" goals for parts they are manufacturing themselves or receiving from outside, and Kaizen, philosophy of continual improvement etc...
Those Japanese invented manufacturing procedures and philosophies are more difficult to adopt today when product models change so rapidly. Every few years motorcycles are completely changed (new or modified engine etc...). Basically, there is no time for reliability improvement of motorcycle parts. They would have to be perfect from day one. Everybody puts too much emphasis on performance nowadays, because it is the primary selling point for products like motorcycles (and their different parts - say Brembo brakes, shocks, switches etc..).