Trading is a mental game. Successful traders know this.
They spend a large majority of their time creating an environment of emotional calm. One of the many ways they do so is by keeping things simple because as anyone who has traded for any length of time knows the markets are complicated.
Successful traders read books that help them hone their mental skills. One such book I recommend is Jim Afremow‘s The Champion’s Mind. 
For instance, here is his take on simplicity.

Keep everything as basic as possible.  Keep the process simple and straightforward.  Be on a focused mission. Specialize. Get rid of the useless “noise”.
Be a Champion Trader.