He wanted to grow a moustache.

He wanted to grow a moustache because it seemed easier than writing his existential detective novel. And possibly quicker. He grew a moustache because he was an admirer of things that required little more than weeks of patience but could be undone in seconds. He grew a moustache because there were no good movies playing in San Francisco. In fact, he did not so much grow a moustache as he subtracted a beard. He grew a moustache because the bearded phase of his life had to come to an end and he wanted to pretend he could set the terms of change. For his face was a ship too long at the dock, so he believed, and whiskers were barnacles to be scraped away to make her seaworthy again. He recalled a time when his nautical metaphors were inspired by Melville, Dumas & Homer, and not by SpongeBob Squarepants.
He grew a moustache because he wanted to have something in common with his favourite detective novelists. He grew a moustache because he wanted to change how he was seen without changing who he was.
"Oh no," his wife said when she came home from work. "At least trim it."
So he trimmed the parts of his moustache that curled under his top lip and tickled his teeth whenever he spoke. He trimmed the parts of his moustache that distinguished the moustache from all the other moustaches he'd ever grown. He trimmed the parts of his moustache he'd grown in hopes of looking like Paco Ignacio Taibo II, but had to finally admit made him look more like a man who didn't know what he was doing when it came to his own face.