Rita Dove, former Poet Laureate of the United States, said: "If you wait for inspiration, inspiration's going to go away and look for more fertile ground to work with."
The Truth Is
Now, I'm only familiar with the "want to write a book" syndrome, but I have a feeling the same thing applies to any aspiration so where I say writer/writing, just insert the words appropriate to the dream of your choice.
If you are an aspiring writer, chances are you view writing as something you do when truly inspired and motivated to succeed. Writers and others call that mindset "communing with the muse." The thing is these people don't know something that professional writers do know.
Inspiration comes to those who write consistently, every day.
Professional writers don't wait for inspiration before hitting the keyboard. We know that the part of the brain that spews words is like an old-fashioned water pump. If you don't know how one of those water pumps work, let me enlighten you.
The pump has a long, cast iron handle. You pump the handle up and down vigorously. After a few seconds of pumping, water spurts out—unless the pump hasn't been used in a long time. If the pump isn't used regularly, you may have to pump and pump until your arm muscles scream in protest, and you're out of breath. It takes a long time for that water to spurt out. Sometimes, you even have to prime the pump by pouring water into it in order for it to start pumping water out again.
Action Begets Inspiration
That's how writing, or any other endeavor, works. You get started and work every day and that creates the motivation and inspiration to keep doing it, day after day. When you write every day, it's easy to get that outpouring of words. But, if you write every now and then, only when you "feel" inspired, it takes a lot longer to get the words flowing.
Many professional writers leave nothing to chance. They prime the pump every day by leaving a dangling thread that can easily be picked up the next day. They also may prime the pump by reading over what they wrote the previous day, editing it a bit, and then diving into the current day's writing.
Sometimes, writers who don't write regularly have a difficult time getting the words to flow. Sometimes the flow is less than a drizzle, only a drip or two. If they give up then, it's even harder the next day.
Sometimes if they don't persist and keep pumping that handle and priming that pump, the flow dries up completely. The longer they go without producing a flow of words—or without taking action toward a goal—the harder it gets to squeeze a word out or make yourself take a single step toward your aspiration of choice.
When that happens, writers call it writer's block. I don't think I've ever heard of a daily working writer with writer's block.
Always remember what Rita Dove said: "If you wait for inspiration, inspiration's going to go away and look for more fertile ground to work with."