Everyone has different tastes, standards and expectations, and so you should only regard reviews as personal opinions which may bear no resemblance whatsoever to what you might think of the same hotel.
If majority opinions are either overwhelmingly positive or overwhelmingly negative, then the decision for you should be easy. But when opinions are fairly mixed, as they are with most hotels, then you just have to seek out comments about the points that are most important to you and use your judgement.
If everyone expresses the same negative opinions about food, or about cleanliness, or about entertainment, etc then it should perhaps set alarm bells ringing and make you look at other options. But where opinions are mixed, look at the dates of the reviews and find some closest to the period of year that you are travelling. Look for the same type of group whether that be couples, parents with kids, etc and then seek out comments on what is most important to you, whether that be location, food, facilities for kids, entertainment, etc.
David