There’s a feeling of dread that surfaces sometimes, when you’ve been working on something a long time and it just doesn’t seem to be successfully presenting the ideas you had for it. The vision you started with hasn’t come to be.
The feeling is often temporary, a loss of confidence we all feel now and then. But if it persists, you have two choices when that feeling arrives: abandon the project, or forge ahead. I can’t say which is best, it’d depend on the circumstances and the work. If you still believe in the vision you had, it’s probably best to live with the feeling for a while, but trust in the vision until the work is done. Only then can you look back with perspective at the whole and decide what serves it and what needs fixing.
If you’ve lost the vision, though, or the connection you had to it, you might do well to move on to something else. I don’t advocate throwing it away, at least not yet. But put it out of sight for a while—a month, a year—and get your newly-refreshed eyes on it later.
Unless we believe in the work, few or no others will. You can show works that you think are less successful, but don’t show anything you don’t believe in or that’s disconnected from your vision.