It's weird, they have that reputation... yet many people still swear by them. I was at the Big Suzuki dealer 3 years back that sells ktm also, lots of them. I spoke with a dude outside beside one of those big 1290 ADV bikes. It was all farkled up, looked nice. I asked him about the reliability stuff, assuming he'd say his had been fine, but it had recently spent 2 months in the dealership over some weird electronic fault. They'd replaced a few components, then the ECU, then the whole wiring harness. I was dumbfounded! It wasn't the first issue he'd had with it either. "That must have Pi$$ed you off" I said. Oh no he replied, I have two of these so I wasn't off the road.
The story only got weirder when I spoke to one of the salesman about their reliability and he went into a sales pitch about how KTM is 120% behind every bike they sell and any issue is fully sorted out fast. Great I thought, but I just want a bike that rarely if ever has any issues. That's when I went off and bought the Yamaha T7 as my first AVD bike. You go to the T7 problem thread on ADVrider and you'll read about issues like. "It's snowing outside, I can ride" "I can't find one for sale"
I've had four RC8's two of which were brand new. The first one broke down on the way home and turned out it was a loose wire. Other than that they were all reliable and spot on.