We've all been there. There isn't enough time in the week, much less today, to get any worthwhile work done on the WIP. Between the distractions of modern life and the hard graft necessary to pay for it, is it so surprising that we have very little left for our stories?
There's long days at work, family needs and wants, social obligations and more. Eventually you fulfill your obligations, at least to the point you don't feel guilty taking an hour or two for yourself. Then it's a battle to actually write, instead of enjoying some well deserved play/sleep time. Constructing a coherent, entertaining, imaginary universe to play in is a big ask at the end of the day.
Trying to squeeze the words out while dog-tired and depressed can be an escape. Stepping out of the real world for a while into your own imagination can be just what you need. I envy those that can manage that on a regular basis. More often, for me at least, it ends with a few tentative sentences followed by a little on-the-fly editing and a guilty check of the word-count. So now you're still tired and depressed, as well as feeling like you've accomplished nothing. Cue guilt and self-loathing.
This is not great conditioning. Pavlov's Writer should salivate at the merest hint of keyboard clicks.
When we first start writing, we expect the magic to happen when we sit at the desk intending to CREATE. Eventually, some later than others (sigh), we discover that the typing/writing/dictating stage is the endpoint.
The story is whirling around in your head, connections made and broken, ideas created, tested and discarded, all part of a process. It can happen in the background while we're going about our day, although generally it's better to be actively engaged. Take the time to daydream about your story, even if it's just a few minutes waiting for the boss's reports to print.
This is the creative side to our chosen medium, coming up with a good, strong story and a framework to hang it all on.
Have fun with it! And...
TAKE NOTES! Have a notebook, dictation app, something to record the moments of brilliance that hit when you're playing around with ideas. Not kidding even a little bit. Napkins? I have notes on toilet paper.
When you do finally have an opportunity to compose your ideas, having those scenes and ideas makes it easier to actually produce. Instead of trying to force a good idea into existence while simultaneously shaping it into a usable form AND attempting to translate your vision for the general public, you can instead concentrate on just the technical aspects/translation.
Polishing your purple prose to communicate in a clear and clever manner, in fact.
It doesn't matter how much time you have for actually writing to start with. You can come up with stories mopping floors, construct scenes while riding the bus, start a rough draft during lunch if the muse strikes (like this post, actually) and spend what writing time you have trying to put the perfect version on the page.
As a bonus there's much less guilt and self-recrimination involved. Telling stories can be fun again.