Soldato
I've heard stories of Karcher owners going through their devices quite often. I think its the lowest end models like the K2 as the motor as not water powered in the K4s and above I believe.
My K4 lasted years before I got my Kranzle for car washing.
I just think its general maintenance which people need do after using their pressure washer, disconnect the water hose, pressure out any remaining water and air till the gun drips water and store away. I think people leave too much water in the machine itself which can clog up with limescale and hard water. I think with general good maintaining you can use the pressure for quite a long time. Also don't use it once and leave it sitting for 6 months before getting it out again. I personally think thats bad practise and waiting for hardware to break.
It's not that complicated sadly. The cheaper ones have plastic parts which crack and leak which cause the pressure valve to open which causes the motor to hunt on and off and eventually fail completely. It's a simple fix if you're prepared to source the relevant part but most people just ditch the washer (and for some reason I personally don't understand) buy another yellow pressure washer. Kärcher make perfectly good pressure washers once you get to a certain price point, and I'd argue that at that price point anyone who knows anything about pressure washers is buying Kränzle and then sourcing the individual fittings from Suttner, QJS etc.