A lot of relatively weighty decisions wind up being made for trivial reasons simply because all of the non-trivial factors cancel each other out - for instance, if I were trying to decide whether to go into ethics or metaphysics (a choice with long-term career impact, assuming I get to be a professor one day) and I didn't find myself strongly preferring one over the other, I could see myself picking one for a silly reason. If my name were Ethel, which it is not, and I liked the sound of "Ethel the ethicist", that might tip the balance. Either that, or contemplating that choice would throw into sharp relief something I'd been overlooking in favor of metaphysics. But if there is no such factor, then why not choose on the basis of "Ethel the ethicist" sounding nice? It arguably makes slightly more sense than flipping a coin.