Personal preference or taste cannot be a parameter to judge art (good or bad), especially without the experience of looking at vast types of artwork. Ability to judge art is a summation of understanding the techniques employed, culture of a time, experience of ones life, feelings etc. Art can only be understood objectively - the artist's aim. Without this understanding, nobody can differentiate between good art and bad art.
Here I must point out that people generally despise modern art due to lack of understanding of the concept. The viewers do not understand that the modern art is more to do with instincts and feelings that can only be felt or experienced. It is not representational. That said, a question can be asked that how many people really even understand representational art? Do they have enough knowledge to understand the symbolism in a representational painting? Rembrandt's 'Return of the Prodigal Son' may look just an ordinary painting to a lot of people unless they are shown what aspects to look at. However, one must know that lack of skills cannot be an excuse to get into modern art just because it looks easier sometimes and leave representational art totally since there is a problem to handle called the 'likeness' in it. Modern art is not at all easy. Years go by just to find the most desired style of painting that connect to the senses of both artist and viewer.