If your intention when buying a stock is to sell it a few weeks later for a quick profit, why trouble yourself with research and after buying, waiting years for something to happen. I've never tried day trading and don't have any desire to, but I can imagine there must be much more thrill and excitement watching stock prices jump from 80 to 95 and down to 70 while working to get in at the low and out at the high. Long-term investors usually don't expect to double their money for five years. The answer is that long term investing is based on sound logic and the evaluation of a company's assets, liabilities, and equity. Short-term trading practices are based more on luck than anything else.
Day traders look for patterns in the past to predict the future.
While the market is generally going up, like during the last several years, it's much easier to get lucky than it is when the market is going down. Over the years, long-term investors will rack up consistent annualized gains and build a great amount of wealth from even small investments. It's called compounding and you've probably heard of it before. It's better to look at long-term results, which include more of the inevitable up and down swings of the economy. That investment will keep growing faster as it grows larger.