Pornography is inappropriate in public and many private places because some people find it offensive, and many others find it at least uncomfortable or awkward to watch in the company of others.
A lot of pornography has explicit content - such as full frontal and rear nudity and intercourse. These are things that most people prefer to keep very private, so it's often deemed inappropriate to watch, especially scenes that are highly unrealistic and could even lead to a negative association of intercourse for boys and girls as they grow older into men and women.
Many parents, too, feel that because it is explicit in nature, their young or teenage children shouldn't be watching it.
Having said this, there are many situations in which it's more appropriate to watch pornography. Some couples, for instance, enjoy watching it together in the privacy of their own homes as a way of exploring their own love lives. It's all about the situation. Sometimes it's okay, but for the most part, its content makes it inappropriate for general viewing.
