Difference Btw BDSM and Rough Sex

BDSM is bondage, discipline, dominance/submission, sadism/masochism, slave/master, etc.

It is not inherently or necessarily sexual or something you do during sex.

• Everything in BDSM is pre-spoken, whereas rough sex develops more instantly. 
• There is a change of power in BDSM it can be physical and mental. There is no requirement to give authority in every case in rough sex. 
• BDSM does not have to have sex in its activities. Rough sex is sex that is rough. 
• Mastery in BDSM requires knowledge and experience. If both physical and mental control are performed with inexperienced persons, there are irreversible consequences. Rough sex is done with everyone who likes it as long as it does not run away. 

They have entirely different definition. Sure, rough sex can be a BDSM activity - but having some overlap doesn't mean they are the same thing.