I would say yes... that it's a perversion of sex... unless its mutual.. and hetero. On the other hand they say masturbation is regarded as part of a child's normal sexual maturity. It only becomes a problem when it takes up time that would otherwise be spent on other things like going out or watching tv or whatever. Essentially its bad when it becomes and addiction.
It is often coupled with porn or sex addiction. But hey people do what makes them feel good... It's harder to convince them that a preoccupation with mindless self indulgence is dangerous.
It's bad because it never truly deals with the emotional triggers, it only creates temporary relief. Many people who indulge in masturbation often have unresolved emotional issues, and masturbation is their coping mechanism. People who feel good about feel good about themselves would only engage in it if its part of the sex act.
I guess the majority of people who do are addicted to some degree, just like any other thing that might make you feel good.
I guess the non-sexual curiosity of it ends before or during puberty, after that its a more consciously sexual habit. I dont think its appropriate for post adolescent adults to be engaging in it, sexual maturity should mean more urge control. Someone once told me its safer than sex, i guess it could be true. lol.
Thats my 1.5 cents.
I hope someone gives an opposing viewpoint.