Most trading strategies do fail during choppy market but succeed during trend (whether bear or bull). Once a trader identifies a trend, the least sensible thing to do would be to ride on it because doing otherwise will be financially suicidal. However, once any strategy begins to make a trader lose money, the best thing would be to take a break away from it in order to reevaluate it. It's not to completely abandon the strategy, anyway.

Well, as for the number of consecutive losses; five will be the alarming figure to make me take a pause.