"It's fun to write something new. It's decidedly not fun to do the grindingly hard work of making existing things better or listening to user complaints and fixing bugs." That's the core of it - and with wider and much more terrifying application than just coding. I wrote about some of that a while back - http://publicstrategist.com/2015/01/nuclear-catastrophes-speeding-tickets-and-agility/ - and came to very much the same conclusion: "The wholly new is grander, more exciting and generally better rewarded. Slowly and painstakingly reducing risk and increasing resilience has much less obvious benefits. Except, perhaps, for avoiding nuclear devastation."