Creativity is an amorphous creature. There is no straight line process from idea or want of an idea to finished work. It is different in almost every meaningful way from a typical job. If you want a job you apply to a company, they interview you, decide to hire you, you show up for work at the determined time, do the job as described by your supervisor, then leave for the day. At the job that sustains me living independently as an adult I put my best into my job and get accomplished what is expected of me. At the end of the pay period I get a check compensating me for the work I have put in. That’s how a typical job work. Most creative work does not work that way.
Unless you are lucky enough to work for a company who produces the kind of things you want to make artistically you have to build all that structure for yourself. It’s a problem of self-organization. It’s building something out of nothing and having no guarantee it will bring anything in return. It’s making creative output on the side while draining your mental energy doing the full-time work that actually pays for one’s survival. I can work for a year on a story and submit it to a dozen different publications and not get anything out of it but rejection. And it isn’t that the rejection is unmanageably difficult to deal with, but the fact that the time spent in creating a thing may have no discernible effect. There will always be some experience gained from the process, but it is essentially impossible to quantify that. It’s like throwing tiny pebbles up against a wall to build a ramp to climb over. Eventually if you throw enough pebbles the hill will be tall enough to get you over the wall. But many of those pebbles will roll down to the bottom of the hill and do nothing to help your cause. At least with the pile of pebbles you can see the hill getting bigger. With creative work you’re essentially doing the same thing, but blindfolded. You never know your hill is tall enough (or even growing) until you are able to get over the wall. It takes a lot of willfully ignoring the appearance of futility to make any progress. There is no way to really know until you’re done. It’s a frustrating way to find a sense of accomplishment with your life. In fact I would tell anyone with the idea of making a living with any kind of art to just give up now. This is not for you. You will spend years inflicting mental damage on yourself, putting yourself into projects that will likely never come to a satisfying conclusion. Just give up.
Now, if you’re one of few for whom that isn’t an option, keep making art.