I bought my LX100 in 2015. I had diligently cleaned the lens barrel before closing the camera. Also, I reasoned that dust could enter the body when the lens was extended via a vacuum effect, so I carefully examined the lens barrel before turning on the camera. All of this worked well; for up to three years there was no discernible dust on the sensor. About three years ago I noticed a thread like sensor occlusion that I accidently dislodged when I dropped my camera while in its case. Of course, the dust was still in the camera body, but I couldn’t see it. Other specks appeared over time, and I tried several techniques, including vacuuming, shaking, blowing, and, dare I say, dropping. None of these worked well. I spent more time than I liked removing the dust shadows in post. Seven years was a good run. I’ll probably keep the camera to offer it to one of my grandchildren.