Most of them use that strategy to try keep the trades safety.
As we know, only put S/L, hedging, martiangle/averaging, .. and cut loss to manage risk :)
To use martiangle/averaging we must reveal where's strong Support/Resistance to come.
I recommend do not use lagging indicators for this strategy.
The weakest creature in the world is a human. It's a reason why the human always develop anything to make them stronger. I am here is just for share, not teaching anyone :)