It depends on a lot of variables, the situation, the context (professional, personal, etc), how much I have invested in something. I don't know if I swing one way or the other. It really depends on the particular situation and everything thats happening when I'm considering cutting my loses as an option.
Its an art to "know when to hold'em and know when to fold 'em, know when to walk away and know when to run". I have found though when I've made the decision to cut my losses and move on it has almost always led me to someplace that expanded my perspective and my life and invariably led me to a place of growth, albeit with a period of freak out in the unknown. This is just what has happened for me. Like [MENTION=1049]knightinbattle said, its probably different for everyone.
At one time I cut my loses in the teaching profession and completely walked away from standardized education. I chose to only teach on a very part time basis in alternative settings because the institutional mindset of education in the U.S. was stifling and oppressive, not only for me as a teacher and individual but for the students, parents and community as well. It was a very difficult decision that ended up being a very good choice for me as far as my mental and physical health. Did I miss some things about teaching in that environment, yes, I missed the kids of course, but also my impact on changing the system. Was it worth it - ABSOLUTELY, why, for my mental and physical well being. Sometimes you just have to make decisions that are about taking care of yourself first.
One thing I have learned though is if it is time to go and you don't listen to the cues. Events will happen that will make it impossible for you to stay. Thats when you get thrown out of where you are whether you want to go or not. The key is recognizing when that time is. I recognize it by the level of difficulty and frustration Im experiencing about hanging in there. Its a scale tipping point for me.