I often tell the story of a guy in Los Angeles that I knew in the 1980s. T-Bonds was the market in those days. Well, this guy only looked to do one trade at the open. He did that trade and then had breakfast and hopped into his Porsche and went to the beach.
Doing the same thing over and over again makes you very good at it, eventually. How long that "eventually" is depends on how much research and testing you do and how structured a trading plan you create. Market Profile for the "where" and a bar chart for the "when" makes the "eventually" a much, much shorter time.
My trade today in the DAX is a good example. The pic tells it all. I have a number of elements in my trading plan and this is one of them.