Like everything else, writing takes time. Authors have busy lives and obligations that must be fulfilled, so they often put off sitting down and putting thoughts on paper. Sometimes they feel that they must obligate themselves to hours at a keyboard to be productive, but that isn't so.
When my six children were young, I learned that you can use small blocks of time efficiently. That habit became very helpful. Many times, I have a thought that I jot down and later develop into a scene. Or I may have fifteen minutes to write one. Once I get the words on paper, I can polish up the writing when I have more time.
We can do more in a few minutes than we think. For example, the other morning before leaving for work, I had about ten minutes. Instead of telling myself that wasn't time enough to do anything, I watered my plants. One more thing not to get in the way of writing later in the day.
Everybody gets twenty-four hours a day; we also get to choose how we use it. Whether that includes wasting it or using it efficiently is totally up to us.