If you think brass swarf is bad, try machining a lot of cast iron. Those pesky tiny fragments get everywhere and find their ways into most chucks. A regular ritual here is at New Years I strip and clean all my lathe chucks and properly lubricate them. Makes a huge difference to smooth working and accuracy.
I had an old and battered Burnerd chuck off the Super 7 which would never hold true and felt rough when I adjusted it so hid it away in a cupboard. I assumed it was simply worn, so that was chuck #1 to get the treatment, so I could figure out how the do the rest. Surprise-surprise it is now almost as good as my expensive replacement. It was full, and I do mean full of swarf from countless years of use. The grease was like concrete. Hence, the anal fascination with cleaning all the chucks in the workshop!