It is definitely simpler to redesign an item rather than create one from scratch. It makes it much easier for me to determine what you are trying to do with the document, logo or website, and how best I can enhance or improve it.

It is also much easier as most of the content has already been collected for the original design. Some of this may be out of date and be in need of an improved image, but the basic framework is there and that can save a lot of time and money.

Redesigning websites is a little more involved, so I need to assess these on a job by job basis. There are limits to how much I can polish something, and sometimes it is cheaper and easier to go back to the drawing board and start again. For the most part, I like to take advantage of an existing design presence and improve on that.