I'm fairly new to doing house jobs myself, so I apologise if this is an unsuitable question here.
I have a ceiling light which has started working only intermittently. I understand from the many answers to similar questions here and elsewhere, that I should be looking for loose connections as a first port of call, which I intend to do. The thing I've not been able to glean from those answers, which I'd like to know before I start looking, is what causes loose connections. I don't want to just 'paper over the cracks' of the problem, I want to solve the root cause if possible.
The switch I can understand, it's turned on and off hundreds of times and any one of them might well be the last straw on a worn connection. But people are suggesting looking at the ceiling rose connections and the junction box. The thing is, no-one's even so much as nudged those. The ceiling rose is completely out of reach and the junction box is in the attic. The light has worked fine for at least ten years and just wouldn't turn on one day, then it turned on fine the next day and has been intermittent ever since.
So my question is, say I open up the switch tomorrow and find nothing wrong there. What should I be looking for in the ceiling rose/junction box that might indicate what actually caused any loose connection I find there to suddenly spring into existence without anyone touching it after ten years of flawless service. As I say, I don't want to just paper over the cracks, tighten up the connection and ignore whatever factor caused it to just 'come loose' all of a sudden.