If you work too hard, you will burn out. The signs of burn out include
loss of motivation, inability to focus, lack of creativity, slow
progress, a feeling of helplessness and general low energy. From time to
time, we all feel one or many of these, but burnout is chronic. You can
function for long periods during burnout, but it won't be satisfying,
and unless you address the root cause, you'll carry on being a zombie.

I
know people who pride themselves on their ability to do regular 60+
hour weeks. I've been one of them even – wearing the 'workaholic' badge
like a right of passage, the hard core willing to make the sacrifices.
And at crunch times, knowing you can kick up a gear and do this for a
sustained period is good. Muscles waste away unless you use them, after
all. But when the long hours become the norm, something is wrong. It's not work, or the market, or this project, or your manager –
it's you. You are becoming addicted to work, failing to take control
and ignoring the other demands on your life.

Like any habit,
burnout hours creep in gradually, then bind you tightly. If it feels odd
leaving your desk and going home at seven, that's a warning sign. Being
productive requires balance in your life – emotional, physical,
spiritual and intellectual. If you are only satisfying a few of your
needs, and exposing yourself to a limited range of experiences and
input, then your output will be similarly restricted. You can't live on a
monotonous diet and expect there to be no side-effects.

The
burnout cycle occurs when your performance starts to tail off, and you
compensate with longer hours. Longer hours lead to lower productivity,
which you combat with yet longer hours. Before long, you are the lights
on/lights off person, topping and tailing at the start and end of each
day. It's a lonely position and eventually you will give up or fail. The
trick is to recognize when this is happening to you, to take
responsibility and to stop it.

Managers are only
interested in output, not hours. They also recognize a burning martyr.
It may feel like you are earning brownie points, but unless the results
are there, it's more likely you are coming across as disorganized.
Instead, take a deep breath, and ask for help. It's likely that with
prioritization, delegation, a few productivity changes, and some training you can
get out on time. This will break the burnout cycle. Own the problem, fix it and you'll find renewed energy and passion for your work.