Definitely. And you need to be careful - you can definitely be too casual and make a mistake that might come up in review (as I did not too long ago). But the

Definitely. And you need to be careful - you can definitely be too casual and make a mistake that might come up in review (as I did not too long ago). But the other side of this is that, by not emotionally investing in the work, you don't also end up feeling hurt and betrayed should you not get the promotion you think you 'deserve'. When I built some beautiful application, but got passed over, it felt like my manager had stabbed me in the back. That's unhealthy. Also, I think that once you internalise the idea that the job was just a job you can become a better performer. You wont feel listless and pointless when a client makes your life difficult, or you are switched from one project to the another. I find that now I just shrug, and tackle what's next.