A woman couldn't sleep one night on account of a loud leaky faucet in her bathtub. She got it fixed the following day by a friend who was a plumber.
The following week she was downstairs working later than usual when she noticed that every time she paused between sentences, the cold tap in her kitchen sink let out a single clear drop. She called up her plumber friend again but she had to wait a couple of weeks before he could get round to the problem.
A month later she started a new job. She sat in the box-like lunchroom and was poured a cup of coffee by a colleague. When this colleague refilled the kettle, she noticed that there were in fact three taps. Apparently the bigger, plastic one was used for hot water. It didn't so much as drip as dribble for a while afterwards. She managed to ignore it for the rest of the day but, before she left, it was dribbling again. She went home with this knowledge and fretted.
She managed to forget about it before going to sleep but instead remembered the taps at her previous workplace, how rusted the handles were and how likely someone would accidentally pull them off someday. This led her to recalling the taps at her father's bungalow and how they groaned along with the pipes in the walls. Following this she remembered the burbling taps in the water fountains at her daughter's high school, the desperate downbursts of water from the taps in her ex-boyfriend's flat and even the faucet that wouldn't stop running at her childhood home.
She relayed all this to her friend who was a plumber and he shrugged his shoulders.
I can't fix all these taps: he said. Nobody can fix these taps unless there's call for it. Call from the owners, that is.
This did not comfort her at all so he changed tact. He asked her: Can you hear any of these taps? Can you actually, genuinely hear these taps dripping? Now? Leaking? Making funny noises?
She thought about this a while and said: No.
So what does it matter? he said. Aside from the taps here in your home, they are all out of earshot.
Then what do you suggest I do?
Forget about it or take up plumbing.
The woman nodded slowly then enthusiastically.
A year passed in blissful contentment. By the end of it she had become a fully-qualified plumber.