Last night the door latch on the kitchen door failed: turning the handle wouldn't retract the latch, so I couldn't get in.
Bad news was the keys to the garage where I keep most of my tools were in the kitchen. Luckily I had a few screwdrivers, pliars etc. lying around. Thank goodness for untidyness.
I took the latch plate off, and found that the square section thing that the bar goes through had disintegrated.It looks like it's made from cheap die-cast metal: the sort of thing you'd expect in a cheap toy.
I ended up getting the latch out after about twenty minutes with a hacksaw, pliars and screwdriver. It's damn annoying that these things are made so cheaply, especially when the failure of that part will lock you out of the room.
Anyway, moan over. Off to screwfix to buy another cheap door catch.