A quote from David Sklanksy's The Theory of Poker:
Any time you make a bet with the worst of it, where the odds are in your favor, you have earned something on that bet, whether you actually win or lose the bet. By the same token, when you make a bet with the worst of it, where the odds are not in your favor, you have lost something, whether you actually win or lose the bet.
Today I took a sell trade on the EUR/JPY from the 5 minute chart, before the actual signal arrived; I had to endure the trade all morning long while it just plodded along against me, but not quite hitting my stop. Whether this trade wins or loses, according to the above quote, I've lost something. I lost a little bit of discipline by getting in too early when I knew I should wait a bit longer.
UPDATE: Yes, I could have gotten out of the early-entry trade right away, but it did give the signal not long after, so I would have been in the trade anyway.
