Most price moves in a trend are not instantaneous reversals into the opposite trend.
I would say that 85% of all price moves, intraday, are moves not in trend.
it is simply higher probability to assume there is no trend.....but that is forex majors.
stock markets similar ...but the probability may not be so high.
this is because forex charts are essentially relative strength charts......but when the two continuously diverge the chart can trend quite spectacularly