Are there some tastes and opinions that you just cannot understand?

Although it is usually a good idea to try and see alternate points of view, I find sometimes that eludes me. For example I cannot understand how someone can do this to a car that used to be nice (although obviously I respect their right to do so). Another example is Freud – every time I have studied his work, I keep thinking to myself “you can’t be serious…”, despite the apparent successes of his theories. Please, no one turn this into a Freud thread now.

What tastes, opinions or ideas can you not understand however hard you try?