I trade with a high win rate. My trades succeed most of the time, therefore it's easy to know when "not to trade", because if they start losing all of a sudden...something is WRONG! Either I've missed a significant market condition change or those days of institutional "adjustments" are happening...option expiration, etc,. I've been doing this a long time too.
That's why I don't lose BIG...I don't trade certain days! Only had to experience this a couple of times to know better.
If your're a "low win rate" trader with good R:R, then taking every trade "mechanically" is probably what you have to do. Your're playing the "math" of profits over time. For me it's different...filters have become a specialty...something I've learned since 1994.
We've all had such an experience, I'm sure. But I argue that it's not the "day" which was at fault, it was the trade initiation and stop discipline at fault
If you take "all trades mechanically, with stops", you won't be a Low Win Rate trader. If you are, then you need to adjust the params for your trades.
I know a good reason...the setup has lost it's "probability to profit" because "everyone" (except the little guys) is WAITING for news to come out.
Unless of course you're Wade Boggs in the dugout after losing the World Series. Which some damn Yankee fan was quick to point out to me the next day and thereafter.