The title is a trick question. To be consistently good is to be great for most of us.
Just showing up is a big part of the work. To show up focused, undistracted, and ready to concentrate our effort on the singular task at hand and be consistent about that will make nearly anything we touch great.
That business venture, learning a new language, being a better husband, father, son, etc... be consistently good and you will be great.
To be consistently good is also considerate of those around you. They can rely on you and they always know what to expect. Think of it as the opposite of a "loose cannon".
Don't underestimate the value of moderate effort consistently applied.