Through discovering and then determining the most effective ways to communicate the discovery, the writing process results in a product an audience can use for pleasure, for information, or as the raw material in his or her own writing and discovery process. Writing has few similarities to manufacturing, which is a process of designing a product, gathering materials needed in the manufacturing process, and then fabricating the product to meet the needs of a consumer or another manufacturing process. But one thing both processes have in common is that neither process is perfect, and an imperfect process results in imperfect products, so one goal of any process, whether writing or manufacturing, is to constantly improve the product by making improvements in the process. One well-established principle that can be applied to writing processes is that variation is part of any process. No one writes consistently well all of the time.
Some people call it inspiration.
One problem with developing writers is that they too often wait for inspiration to begin writing. If all writers waited for the muse to inspire them, few words would ever be written. Inspiration is a very small, even miniscule part of writing. Writing takes work, not just inspiration, and that work is often uneven because writing is a process and variation is part of any process. The reality of variation in processes is one reason it is very important to give a writing task time.