1.It installs a library of porno in your head-you literally have access to almost every porno you have ever watched
this corrupts the brain and makes you see women as tools for sex
2.It screws up marriage-before or during marriage it can mess you up.before marriage it will give you a unrealistic view of sex.during marriage you might just watch a porno instead of having sex with your wife. It might also make your wife unattractive to you. You would prefer the fake women in porn.
3.It might effect your time-You know you have a problem when you spend hours viewing porn instead of doing the task at hand.
4. Its haram. Now that i think about it, this should be number. After viewing all these naked people it will be hard for you to lower your gaze.
After defeating porn, there's another big on out there masturbation. They might go hand in hand

So brothers and sisters lets try to stop this sin before its too late.