Here is a very short list of comments from very reliable sources—successful professional traders.

From my collection of Books

 John F. Carter: “It is important to remember that there is no need to spend wasted years looking for complicated setups or the next Holy Grail.  There are very simple setups out there to use.  Some of the best traders I know have been trading the same setup, on the same time frame, on the same market for 20 years. They don’t care about anything else, and they don’t want to learn about anything else.  This works for them, and they are the masters of this setup.  They have nothing else coming in to interfere with their focus” (p. 31, Mastering the Trade: Proven Techniques for Profiting from Intraday and Swing Trading Setups).

Clifford Bennett: “While there have been some spectacular front-cover traders, the ones who amass fortunes year after year tend to stay in the background. At the very least, they display a simple and down-to-earth approach to markets if they are ever interviewed” (p. 117, Warrior Trading: Inside the Mind of an Elite Currency Trader).

Mark Douglas: “What you want to do is become an expert at just one particular type of behavior pattern that repeats itself with some degree of frequency. To become an expert, choose one simple trading system that identifies a pattern, preferably one that is mechanical, instead of mathematical, so that you will be working with a visual representation of market behavior. Your objective is to understand completely every aspect of the system-all the relationships between the components-and its potential to produce profitable trades.  In the meantime, it is important to avoid all other possibilities and information” (pp. 208-09, The Disciplined Trader: Developing Winning Attitudes).

Marcel Link: “Systems should be kept as simple as possible. Overdoing things doesn’t make a system better; on the contrary, it can take away from a good system.  Trying to make a system too complicated with too many indicators and variables is a common mistake with some traders: some of the best systems are the simplest. As a rule of thumb, a system should fit on the back of an envelope and be easily explained so that someone can understand what every indicator does and every rule does.  Otherwise it’s too complicated.  Always remember the old adage ‘Keep it simple, stupid’ and you’ll be okay” (p 249, High Probability Trading).

George Angell: “One observation I’ve made over the years, which is especially notable on the trading floor, is that everyone who truly succeeds is a specialist. Unlike the novice trader, who may dabble in as many as a dozen different futures contracts, the professional floor trader is identified with just one kind of futures and one specific type of trading…moreover, the professional is identified by his specialty-scalper, short-term trader, spread trader, or whatever.  He does the same thing every day (pp. 10-11, Sniper Trading).

John Murphy: “My work has gotten better due to simplifying my approach.” (KEY TO SUCCESS)

Dennis Gartman: “Keep your technical systems simple. Complicated systems breed confusion; simplicity breeds elegance.” (From Dennis Gartman’s Trading Rules List, Rule #12).