Avoid Overcomplicating Things

Most tracks don't die because the idea was bad. They die because the producer started rendering the details before the idea had properly taken shape.
You know the trap, because everyone who's tried to finish a song has fallen into it. You sit down with something promising, and within twenty minutes you're bussing out drum channels, splitting the bass into sub and mid layers, agonizing over the exact reverb tail on a hat — on a part you're not even sure belongs in the track yet. You keep adding. You can't tell whether the mix is full enough or already too full. And somewhere in all that meticulous, well-intentioned work, the thing that was actually good about the idea quietly slips away.
The single biggest fix I can give you is to break your workflow into distinct phases and refuse to let them bleed into one another. Sound design is one phase. Sketching is another. Detailed composition is a third. Don't do them in the same session. Frankly, if you can manage it, don't even do them on the same day. First, you design or collect your sounds. Then you sketch with those sounds, leaning on placeholders wherever you need to, until you feel the idea starting to come together. Only then do you move into the details.
The reason phase-mixing wrecks tracks is that each of those jobs pulls your brain in a different direction, and you can't be in two of those headspaces at once. Sound design is fiddly and technical — you're deep in a synth, chasing a tone. Sketching is fast and loose — you're chasing a feeling, and the worst thing you can do is stop to perfect anything. Detailing is patient and obsessive. Try to do all three at the same time, and what actually happens is the technical, perfectionist part hijacks the loose, feeling-driven part, because precision always feels more productive than play. You get the satisfying sense of progress — channels bussed, levels set, a hi-hat dialed in — while the thing that mattered, the actual idea, never got a chance to prove whether it was going anywhere. And the hardest discipline in all of it is exactly the one that protects against this: getting comfortable leaving parts unfinished on purpose, while you wait to see whether the idea is even worth developing. Most people can't stand the unfinished part. That's the whole problem.
Sketch before you render
There's a way of thinking about this in terms of drawing that makes it obvious.
Sound design is mixing the colors on your palette. It's so much easier to work when the exact color you need is already sitting there at your fingertips, instead of having to stop mid-stroke and shift gears to mix it. Get your sounds ready first, as their own task, so that when you're composing, you're reaching for something that already exists.
Sketching is the next thing entirely. When you draw, you don't spend hours grinding every shadow and line into one corner of the page while the rest of it sits blank. You'd never see whether the composition works. You rough in the whole thing first — get the overall shape right — and only after that do you start rendering the detail. Music is no different. Use shortcuts to rough in the parts until you start feeling the vibe you're chasing. Don't get precious about bussing things out and separating channels "the right way" too early. Stuck meticulously programming a drum line? Drop in a loop instead and get the feeling of the drums first; you can always detail them later. Losing your inspiration while hunting for the perfect synth tone? Sketch the part with a preset that's kinda in the neighborhood and move on.
It's fine for things to be rough in the early stages. The goal isn't a finished part — it's getting to the moment where you can make an honest go / no-go call on the whole idea. That decision is the thing the rough sketch exists to serve. You can't judge an idea fairly when half of it is rendered to a mirror shine and the other half is empty space; your ear gets seduced by the one polished corner, and you keep a track that should have died, or you trash a great idea because the one part you happened to detail wasn't working yet. Get the whole thing roughed in at the same low resolution, and you can actually hear what you've got. Work fast, get it to that decision point, and then (only then), is it time to get nerdy with the details. By the time you arrive there, you'll have something most people never give themselves: a clear picture of what actually needs doing, and what never did.