Quality is pretty self explanatory – good, well written copy or well produced videos that exude professionalism and authority.
Relevance is also pretty straight forward. If the user is searching on “cars” and you’re your site is about “boats”, clearly it is not relevant. Now obviously that example is oversimplified, but you can infer that the more specifically relevant your content is to what the user is searching for, the more success you will have in bringing those users to your site via Google. Uniqueness is a bit more esoteric.
Uniqueness has most of the costs associated with it. Both being time and/or money. However, there are two fundamental methods you can apply to creating unique content.