Well thanks everyone, very construtcive indeed good advice for me and any one else who will come across this thread at some time.
Key points are:
Yes you are right, sometimes you'll not exit when you should, sometimes you'll even average a losing trade, something will happen in the market, you'll make money and it sticks in your mind.
Of course these ocassions are outweighed by the times you lose your shirt.
What always sticks in my mind is in an idea in a trading book, I forget which one, which states it's human nature to want to be right a lot and then wrong once get over that and get back to being right.
In trading this can translate in to my problem of taking lots of small profits, maybe even 99% right in a week only to come across the one loser that wipes it all out. Maths wise I'm down but I've felt good 99% of the time and bad for shorter time. I repeat the pattern over and over.
As Charlton says too the very under used idea of opp cost of hanging on a loser.
I have, in the past (i'm an intra day trader) held on to a loser averaging down sometimes for as long as three months and found my self in a real state. Even if by miracle it has come back to get me out at even or so I look back at not earning for three months and it makes me sick.
I could have taken the small loss, moved on,made money for three months and it would be long forgotten.
All great points to consider.
I'll tell you what I am trying.
I no longer 'match' trades in my spreadsheets just list them in time order. Before I would say I B@X S@Y there fore made y-x on that trade it was a 'winner' or a 'loser'.
Now I just open and close as I see fit and only give a daily total.
This is a small trick but it stops me trying to break even on a trade, or not wanting to take a loss as I've had no losers all week etc. I just try to do the right thing and at the end of the days weeks and month it add up to profit.
Maybe this will work for anyone reading this who doesn't like to lose and gets hung up in 'if I can just get back to even I'll exit'. Why? It you're losing get out, reverse even, and if you are lucky to see the market come back your way why exit at even, perhaps you are right and it will go further.
Any other methods people use to make sure when they know they should be out, they actually are out?
Stephen McCreedy