Agreed Alfred. A splendid fit for purpose design unsullied by passwords or interminable feature updates you never asked for.
I think we are meaning the same thing by cleaning - removal of encrusted gunk that stops the lid operating easily, strains hinges trying, blocks airways and builds up a layer of waste crud. But not aspiring to bright metal. My current copper model (a kind gift) is too soft to withstand excessive heat or bashing about. My previous steel one was more robust in that regard and my next firebox will probably be steel.
I often leave it ticking over on one side without actual puffing for long periods and that probably leads to tar depositing.
When you see some folks kit, it’s often in pretty poor shape and barely serviceable. I always remember the wry bee inspector comment about his surprise in seeing the long queues for buying new kit at shows. All he ever saw being used doing his rounds was old stuff on the point of collapse.