My outdoor tap seized up and wouldn't close. It was gushing water. I bought a new one and replaced it. It's a cheap one from Bunnings (link, but male instead of female), screwed on to the pipe with plumbing tape in the thread.
This one has worked well for a few months, but now it too is starting to seize up. It isn't gushing, just trickling, but it won't close completely. If I open it completely, spray WD-40 on it, and close it, it will stop flowing, but this only lasts for a few uses before it won't close completely again.
The house was built around 1996. The water source is metropolitan mains water (Melbourne, Australia) which is reliable. It's only this tap in the house that fails.
What could be causing this? What can I do to fix this permanently?