The author starts it right: “Do what you love. Love what you do.”
Just to build an entire case on half-the-thought: DWYL...
I've read the comments and that first part (DWYL) is practically the only thing people are discussing, but I believe it loses the bigger picture.
DWYL. LWYD. - Both things make it balanced. It's not only about DWYL. When you have to do something else, you need a conscious effort and purpose to LWYD.
I've read some years back (can't remember the name of the book) written by a chinese talking about his father that was a locksmith and got a job as street sweeper. He faced it with an intent. He'd be the best street sweeper in China. He would love the streets assigned under his care. That is the LWYD. That takes commitment and guts. But when you LWYD, you also DWYL.