Very true. I like to set my stops just below the nearest support or just above the nearest resistance. Then, after I've determined my stop, I determine my position size based on the amount that I'd be risking, or the distance from my entry to my stop. Never do I set my stops based on how much I want to risk, because as naifwonder said, the market doesn't care. Always better to set your stops based on factors that the market responds to, such as recent price action. Plus, if my reason for entering a trade is based on a particular support level, if price drops below that level of support, there's no longer a reason for me to be in that trade and it's time to get out.