My job as a facilities maintenance engineer required a wide range of skills. One day I might have to fix the furnace, while the next day could see me painting the CEO’s office. When I described it to a ­coworker as “I’m a jack of all trades, master of none,” I was amused, yet slightly offended, when she offered a less than complimentary interpretation from her native Cantonese: “Equipped with knives all over, yet none are very sharp.”