Having more than 1 trading system

Hi Pat. In Dr. Van Tharp's book, he says there is no trading system that can work well in all market types, so traders need to determine the current market as well as having a different system for each market cycle. So far in this choppy volatile market, a lot of breakout setups fail and stocks end up retrace back to their pivots after a few percents move, except for very few names like NVDA that I missed. I want to ask why you mostly focus on simple flat base breakout even in this type of market without changing/having another system?