... why? ...
Because at the extremes one is able to find opportunities for entry with a small risk relative to its potential profit, moreover if you are wrong in the initial hypothesis is easy to scratch the trade and be ready for re enter the market
.... therefore be ready to pull the triggered depending on your strategy and look for the continuation of the down movement or the false break out of the support, in any case right now I would be looking to enter short only if there are followers below the most immediate Swing Low
However is important to mention that as a trader one should always be looking to the bigger picture and one can see that after a failed attempt to keep pushing higher (Previous Uptrend Channel) now the sellers are testing if there are some follow through to the downside, notwithstanding there is not much conviction and a possible congestion could be going on(extremes are defined with the blue lines in the chart)